FiledMay 26, 2026 - 8:41 AM ET

SSMRSunshine Silver Mining & Refining CoNYSE

Sunshine Silver S-1/A for NYSE IPO: 20M shares, $13.50–$16.50 range

S-1/AIPO / ListingneutralImpact60

SSMR Price

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N/A$0.00 (+0.00%)

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Why It Matters

The filing advances Sunshine Silver toward a public listing while creating concentrated voting control and issuance-related dilution risks

Summary

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Sunshine Silver filed Amendment No.1 to its Form S-1 registering a firm-commitment IPO of 20,000,000 common shares with a $13.50–$16.50 per-share range. The company says it has been approved to list on the New York Stock Exchange under ticker SSMR. Electrum Group would control approximately 60.7% of voting power after the offering

Score60

Score Rationale

neutral

S-1/A includes price range and listing approval

Bullish

NYSE listing approved
Firm-commitment underwriting
Price range implies material valuation

Bearish

Electrum to control ~60.7% voting power
No prior public market for common stock
Potential dilution from outstanding warrants and financing

Key Evidence

Prospectus: 20,000,000 shares to underwriters, firm commitment
Prospectus: IPO price range $13.50–$16.50
Prospectus: Electrum will control ~60.7% voting power

What To Watch Next

SEC effectiveness and final prospectus filing (Form 424B4)
Final IPO pricing and share allocation announcement
Underwriters' 30-day over-allotment exercise decision

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SSMR Market Context

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Original Filing Text

SEC filing text preserved from the raw item store.

### S-1/A - S-1/A
S-1/A
1
ny20061035x5_s1a.htm
S-1/A

TABLE OF CONTENTS
As filed with the Securities and Exchange Commission on May 26, 2026.
Registration No. 333-295768

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 1

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

SUNSHINE SILVER MINING & REFINING COMPANY

(Exact Name of Registrant as Specified in Its Charter)

(State or Other Jurisdiction of

Incorporation or Organization)
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| 1040

(Primary Standard Industrial

Classification Code Number)
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| 85-3794822

(I.R.S. Employer

2209 Big Creek Rd

Kellogg, Idaho 83837

(208) 783-1700

(Address, Including Zip Code, and Telephone Number, Including

Area Code, of Registrant’s Principal Executive Offices)

Heather White

Chief Executive Officer

Sunshine Silver Mining & Refining Company

2209 Big Creek Rd

Kellogg, Idaho 83837

(208) 783-1700

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

Copies to:

Alejandro Gonzalez Lazzeri

Jeremy Winter

Skadden, Arps, Slate, Meagher & Flom LLP

One Manhattan West

New York, NY 10001

(212) 735-3000
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| Michelle Shepston

General Counsel

Sunshine Silver Mining & Refining Company

2209 Big Creek Rd

Kellogg, Idaho 83837

(208) 783-1700
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| Jorge U. Juantorena

Lesley Janzen

Jonathan Mendes de Oliveira

Cleary Gottlieb Steen & Hamilton LLP

One Liberty Plaza

New York NY 10006

(212) 225-2000
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Approximate date of commencement of proposed sale to the public:

As soon as practicable after the effective date of this Registration Statement.
If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ☐
If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

TABLE OF CONTENTS
The information contained in this preliminary prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.
SUBJECT TO COMPLETION, DATED MAY 26, 2026
PRELIMINARY PROSPECTUS
20,000,000 SHARES

SUNSHINE SILVER MINING & REFINING COMPANY

COMMON STOCK

We are selling 20,000,000 shares of common stock to the underwriters in a firm commitment offering.
Prior to this offering, there has been no public market for our common stock. We currently estimate that the initial public offering price will be between $13.50 and $16.50 per share. We have been approved to list our common stock on the New York Stock Exchange (the “ NYSE ”) under the symbol “SSMR.”
The underwriters have an option to purchase a maximum of 3,000,000 additional shares of common stock from us to cover over-allotments. The underwriters can exercise this option at any time within 30 days from the date of this prospectus.
We are an “emerging growth company” as defined under the federal securities laws and, as such, are subject to certain reduced public company reporting requirements for this prospectus and future filings. See “ Prospectus Summary—Implications of Being an Emerging Growth Company .”
The Electrum Group LLC (together with its affiliates, “ Electrum ”) will control approximately 60.7% of the voting power of our common stock outstanding upon completion of this offering (or approximately 59.5% if the underwriters exercise their option to purchase additional shares of our common stock from us in full). As a result, we will be a “controlled company” within the meaning of the corporate governance rules of the NYSE, and we have elected not to comply with certain corporate governance requirements otherwise applicable to listed companies. See “ Management—Controlled Company Status .”

Investing in our common stock involves risks. See “ Risk Factors ” beginning on page 29 of this prospectus.

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Public offering price
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Underwriting discounts and commissions (1)
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Proceeds, before expenses, to us
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(1)

| See “ Underwriting and Plan of Distribution ” for a description of compensation to be paid to the underwriters.
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Delivery of the shares of common stock will be made on or about , 2026 through the book-entry facilities of The Depositary Trust Company.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
Joint Lead Book-Running Managers

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Morgan Stanley
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The date of this prospectus is , 2026.

TABLE OF CONTENTS
TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS
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PROSPECTUS SUMMARY
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THE OFFERING
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SUMMARY CONSOLIDATED FINANCIAL DATA
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RISK FACTORS
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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS
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USE OF PROCEEDS
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DIVIDEND POLICY
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CAPITALIZATION
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DILUTION
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MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
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INDUSTRY OVERVIEW
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BUSINESS
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MANAGEMENT
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EXECUTIVE AND DIRECTOR COMPENSATION
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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS
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PRINCIPAL STOCKHOLDERS
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DESCRIPTION OF CAPITAL STOCK
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U.S. FEDERAL INCOME TAX CONSIDERATIONS FOR NON-U.S. HOLDERS OF COMMON STOCK
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SHARES ELIGIBLE FOR FUTURE SALE
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UNDERWRITING AND PLAN OF DISTRIBUTION
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LEGAL MATTERS
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EXPERTS
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WHERE YOU CAN FIND MORE INFORMATION
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GLOSSARY OF TECHNICAL TERMS
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INDEX TO FINANCIAL STATEMENTS
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| F-1
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Through and including the 25th day after the date of this prospectus, all dealers that effect transactions in shares of our common stock, whether or not participating in this offering, may be required to deliver a prospectus. This is in addition to the dealers’ obligations to deliver a prospectus when acting as underwriters and with respect to their unsold allotments or subscriptions.
We and the underwriters have not authorized anyone to provide any information other than that contained in this prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We and the underwriters take no responsibility for, and can provide no assurance and make no representation as to the reliability of, any other information that others may give you. We are offering to sell and are seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The information contained in this prospectus is accurate only as of the date of this prospectus, regardless of the time of delivery of this prospectus or of any sale of our common stock.

TABLE OF CONTENTS
ABOUT THIS PROSPECTUS
Unless the context otherwise requires, the “ Company ,” “ we ,” “ us ” and “ our ” refer to Sunshine Silver Mining & Refining Company and its consolidated subsidiaries.
The discussion of our financial condition and results of operations should be read together with our audited consolidated financial statements for the years ended December 31, 2025 and 2024 and our unaudited consolidated financial statements for the three months ended March 31, 2026 and 2025 prepared in accordance with U.S. generally accepted accounting principles and the related notes and the other financial information included elsewhere in this prospectus.
Certain figures and percentages included in this prospectus have been subject to rounding adjustments, and all quantities of Mineral Resource estimates are rounded to the appropriate number of relevant units. Accordingly, totals and sums presented in this prospectus may not add up due to rounding.
Unless otherwise indicated, all references to “U.S. dollars,” “dollars” and “$” in this prospectus are to the lawful currency of the United States of America. All references to ounces in this prospectus are to troy ounces, unless otherwise specified.
MARKET AND INDUSTRY DATA AND FORECASTS
This prospectus includes market and industry data and forecasts that we have developed from independent research reports, publicly available information, various industry publications, other published industry sources or our internal data and estimates. Independent research reports, industry publications and other published industry sources generally indicate that the information contained therein was obtained from sources believed to be reliable, but do not guarantee the accuracy and completeness of such information. Although we believe that the publications and reports are reliable, neither we nor the underwriters have independently verified the data. Our internal data, estimates and forecasts are based on information obtained from trade and business organizations and other contacts in the markets in which we operate and our management’s understanding of industry conditions. Although we believe that such information is reliable, we have not had such information verified by any independent sources.
We refer in this prospectus to information and estimates from the antimony market report entitled “ Antimony Market Assessment ” prepared by Argus Media (“ Argus ”) in December 2025 (the “ Argus Report ”), the antimony plant report entitled “ Sunshine Silver Mining & Refining Corporation Antimony Plant Viability Summary Report ” prepared by Samuel Engineering, Inc. (“ Samuel Engineering ”) in April 2025 (the “ Samuel Engineering Report ”) and the Sunshine Silver/Copper Refinery report entitled “ Silver Refinery Process Study and Class V Estimate ” prepared by trajectorE Engineering, Inc. in November 2025 (the “ trajectorE Report ”). Each of these reports was commissioned by us.
NOTICE REGARDING MINERAL DISCLOSURE
The Technical Report Summary for our material property, the Sunshine Mine (as defined below) (the “ Sunshine Technical Report Summary” ), has been prepared by SLR International Corporation (“ SLR ”) and SRK Consulting (U.S.), Inc. (“ SRK ”) in accordance with subpart 1300 of Regulation S-K (“ S-K 1300 ”) and is included as Exhibit 96.1 to the registration statement of which this prospectus forms a part. The Mineral Resource estimates contained in this prospectus were prepared in accordance with S-K 1300 with an effective date of February 24, 2026 and have not been updated since that time.
This prospectus refers to estimated Mineral Resources, including Inferred Mineral Resources and Indicated Mineral Resources. See “ Glossary of Technical Terms ” for the definition of those terms. The estimates include mining dilution and mining recovery. Mining dilution and recovery factors vary and are influenced by several factors including deposit type, deposit shape and mining methods. The Mineral Resource estimates contained in this prospectus may be materially affected by changes to the geological, geotechnical and geometallurgical models, infill drilling to convert material to a higher classification, drilling to test for extensions to known Mineral Resources, collection of additional bulk density data and significant changes to commodity prices, and by environmental permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.
Inferred Mineral Resources are subject to significant uncertainty as to their existence and as to their economic and legal feasibility. The level of geological uncertainty associated with an Inferred Mineral Resource is too high to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability.

TABLE OF CONTENTS
Unless the context otherwise requires, all references in this prospectus to “Qualified Person(s)” are to Qualified Persons as defined in S-K 1300. Our disclosure relating to Mineral Resource estimates and exploration results is based on supporting documentation prepared by Qualified Persons. The Sunshine Technical Report Summary has been prepared by Qualified Persons, as described herein.
QUALIFIED PERSONS STATEMENT
The scientific and technical information related to the Sunshine Mine contained in the Sunshine Technical Report Summary and reproduced in this prospectus, including Mineral Resource estimates, capital costs, operational costs and economic analysis information, has been approved and verified by SLR and SRK. Drill hole results from the recent infill and exploration drilling at the Sunshine Mine that are included in this prospectus have been approved and verified by SRK. Both SLR and SRK are Qualified Persons under S-K 1300. Neither SLR nor SRK is affiliated with us or any other entity that has an ownership, royalty or other interest in the Sunshine Mine.
All references to Scout Discoveries Corp. (“ Scout ”) and the work performed by Scout in this prospectus, including without limitation all scientific and technical information under the heading “ Business—Selected Exploration Results from Rock and Soil Geochemical Data ” on page 79 , have been reviewed and approved by Amanda Irons, who is a Qualified Person under S-K 1300. Ms. Irons is a licensed Certified Professional Geologist (CPG-12166) under the association of the American Institute of Professional Geologists, and is an employee of Scout. Ms. Irons’ employer, Scout, is an affiliate of the Company. Electrum owns approximately 32% of Scout. See “ Certain Relationships and Related Party Transactions—Exploration Services Agreement .”

iii

TABLE OF CONTENTS
PROSPECTUS SUMMARY
This summary highlights information contained elsewhere in this prospectus. This summary may not contain all of the information that you should consider before deciding to invest in our common stock. You should read this entire prospectus carefully, including the “Risk Factors” section and our consolidated financial statements and related notes included elsewhere in this prospectus.
The Company
We are the owner and developer of the permitted Sunshine mine (the “ Sunshine Mine ”) and permitted silver/copper refinery located one mile north of the Sunshine Mine (the “ Sunshine Silver/Copper Refinery ”), as well as the associated facilities including a tailings storage facility (the “ Sunshine Tailings Storage Facility ”) and historical antimony refinery grounds (collectively, the “ Sunshine Complex ” ) . The Sunshine Mine is a historic, permitted, large-scale past-producing silver mine in the United States, which historically also produced meaningful quantities of antimony, copper and lead. The Sunshine Mine is one of the highest-grade primary silver resources in the world, with an average diluted silver grade of 1,022 grams per tonne of Indicated Mineral Resources and 776 grams per tonne of Inferred Mineral Resources. When production is restarted, we expect the Sunshine Mine will also be one of the largest silver mines in the United States. We have the major permits required to restart mining, milling and refining operations, and we will not require an environmental impact study to initiate restart of such operations. We do not anticipate issues in maintaining our current permitting status or securing the outstanding and ongoing permits required. A summary of relevant permits and their status is included in Table 17-1 of the Sunshine Technical Report Summary. Our current permits will be subject to normal course updates throughout the construction process. Our mining, milling and refining complex includes substantial installed infrastructure, including approximately $208 million of investments that we have made over the last 16 years to maintain and modernize the Sunshine Complex and to consolidate the highly prospective land package surrounding the Sunshine Mine. We plan to restart operations at the Sunshine Complex in 2028.
Although not currently defined as part of the existing resource or economics, we plan to produce antimony, as well as copper and lead by-products, once operations restart at the Sunshine Mine. The silver-bearing mineralization (tetrahedrite) at the Sunshine Mine has historically contained economic quantities of antimony, as demonstrated by decades of antimony production at the Sunshine Complex, which processed concentrate from the Sunshine Mine and other mines. Antimony production from the Sunshine Complex supported the U.S. war effort during World War II, and between 1953 and 2001, the Sunshine Complex produced over 48.4 million pounds of finished antimony. A potential new antimony facility at the Sunshine Complex (the “ Sunshine Antimony Plant ”) could allow us to process antimony-bearing concentrate from the Sunshine Mine and toll-process external (third party) antimony-bearing concentrates, which together could provide a pathway for the Sunshine Complex to become one of the most significant centralized hubs for producing refined antimony in North America.
We have commenced early-stage sampling and testing of material from the Sunshine Complex to evaluate for the potential presence and recovery of other critical minerals such as gallium and germanium to support the possible future production of these other critical minerals. Silver, antimony and other critical minerals like copper, lead, gallium and germanium are required in applications with significant relevance to national security, industrial revitalization and energy independence. Silver is the best metallic conductor of electricity and is used in photovoltaic cells, electronics, electric vehicles, sensors and corrosive-resistant welding and, like gold, as a store of value. Antimony is used for munitions production, flame retardants, batteries, semi-conductors and other key defense applications. Copper is essential for electrification and energy transition, while lead is required in energy storage and national defense applications. Gallium is essential for the production of 5G mobile telecommunications infrastructure, data center electronics, LED lights and laser diodes, high-efficiency solar cells and advanced defense and telecom systems, while germanium is essential for the production of fiber optics, infrared optical systems, solar cells and radiation detectors.
Large, primary silver mines are rare, with only approximately 26% of global mined supply coming from primary silver mines in 2025. Additionally, the universe of primary silver companies is small – a reality exacerbated by recent consolidation among public silver mining companies, including Pan American Silver Corp.’s acquisition of MAG Silver Corp. in September 2025, Coeur Mining Inc.’s purchase of SilverCrest in February 2025 and First Majestic Silver Corp.’s acquisition of Gatos Silver in January 2025. Silver supply is largely driven by mined silver production, which accounted for approximately 78% of total silver supply in 2025. Mined supply is sourced primarily from Mexico, China and Peru, which accounted for approximately 49% of global mined supply in 2025, compared to only approximately 4% from the United States.

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Although the United States is estimated to contain significant quantities of critical Mineral Resources, decades of foreign outsourcing have created a heavy reliance on other nations, especially China, for processing and supply. Specifically, while China accounted for 13% of global mined silver supply in 2025, it controlled the refining of approximately 60% to 70% of the global supply of silver. Driven by national security and economic security considerations, the United States is now actively working to bolster domestic critical mineral production, create a more favorable permitting environment to make U.S. mining and processing more competitive globally, and reduce its dependence on other nations. Most notably, the U.S. Department of the Interior’s “List of Critical Minerals” serves as a blueprint for the U.S. government’s objective to secure supplies of materials needed for defense, manufacturing and clean energy technologies. Silver was recently added to the list, joining other critical minerals which may also be present at the Sunshine Mine including antimony, copper, lead, gallium and germanium. Inclusion on the “List of Critical Minerals” is significant because it identifies minerals that the U.S. government deems strategically important and may inform federal prioritization for research, permitting, national stockpiling and incentive or funding programs designed to strengthen domestic supply chains.
Principal Asset
Our principal asset is the Sunshine Complex. The Sunshine Antimony Plant, which we may develop depending on the outcome of our anticipated antimony Feasibility Study, would also make up part of the Sunshine Complex. The Sunshine Complex is located in the Coeur d’Alene Mining District (also known as the “ Silver Valley ”) in Idaho, the most prolific silver district in U.S. history, which hosts many past-producing and currently operating mines along an approximately 12-mile belt. The Silver Valley is a mining-friendly region of the United States with immediate access to transportation, water and low-cost, renewable electricity. The region benefits from favorable mining regulations, an existing skilled labor force, mine suppliers and strong support for mining from the local population and government. We are the largest mineral rights holder in the Silver Valley. We own and control 9,561 hectares of a highly prolific, underexplored and newly consolidated district-scale land package around the Sunshine Mine.
Location of the Sunshine Mine within the United States and the Silver Valley

The Sunshine Mine is estimated to have produced approximately 365 million ounces of silver between its initial production in the early 1900s and the cessation of production in the early 2000s. Over the last five full years of production from 1996 to 2000, the Sunshine Mine produced ore containing 23.0 million ounces of silver, 4.7 million pounds of antimony, 5.7 million pounds of copper and 38.4 million pounds of lead, with average metallurgical recovery of 97%, 97%, 97% and 93%, respectively. We have the major permits required to restart mining, milling and refining operations, and we will not require an environmental impact study to initiate restart of such operations. We do not anticipate issues in maintaining our current permitting status or securing the outstanding and ongoing permits required. A summary of relevant permits and their status is included in Table 17-1 of the Sunshine Technical Report Summary. Our current permits will be subject to normal course updates throughout the construction process.
We expect that, following the contemplated conversion to a dry stack tailings storage facility, the Sunshine Tailings Storage Facility will have sufficient capacity to support tailings production for the entirety of the mine life envisioned in both the Base Case of the Sunshine Technical Report Summary, which envisions a 24-year mine life and assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, and the Indicated Only Case of the Sunshine Technical Report, which envisions a 10-year mine life and assumes the mining of only Indicated Mineral Resources. We are one of the few U.S. mining companies with a vertically integrated mine to mill to refinery platform, enabling potential onsite production of silver eligible for the COMEX global futures and commodities marketplace. Given the limited domestic refining capacity for silver, this integration provides a strategic advantage in supplying U.S.

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industrial and investment demand. Additionally, we have all major permits required for antimony production, which could enable us to produce a suite of finished antimony products using antimony feed from the Sunshine Mine and other mines in the United States, which could provide additional revenue opportunities beyond our own mining and milling operations. We are undertaking a Feasibility Study for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery, and we are also undertaking a Feasibility Study for the development of the Sunshine Antimony Plant as part of our technical evaluation ahead of a potential decision to pursue the development of the Sunshine Antimony Plant. In parallel with these Feasibility Studies and based on the results of these Feasibility Studies, we may evaluate external financing alternatives and strategic transactions with respect to the Sunshine Silver/Copper Refinery and the Sunshine Antimony Plant.
The Sunshine Mine includes substantial installed infrastructure, including approximately $208 million of investments that we have made over the last 16 years to maintain and modernize the Sunshine Complex and to consolidate the highly prospective land package around the Sunshine Mine. Notable existing underground development comprises two shafts, three hoists and three adits, which allows multiple paths to access the underground, as well as the flexibility to cost-effectively ramp up production rates if further Mineral Resources are discovered, especially in the highly prospective Upper Country (as defined below) area. The Sunshine Complex also has the Sunshine Tailings Storage Facility, the Sunshine Silver/Copper Refinery, power transmission grids and other fixed equipment, all of which may lower capital costs and timeline to production. In total, we estimate that it would currently cost approximately $600 million to replace this existing infrastructure, and we also believe it could take several years to obtain the requisite permits.
Selection of Existing Underground and Surface Infrastructure

The Sunshine Mine is one of the highest-grade primary silver deposits worldwide, with an estimated 103.9 million ounces of Indicated Mineral Resources at average diluted grades of 29.8 ounces per ton and 159.8 million ounces of Inferred Mineral Resources at average diluted grades of 22.6 ounces per ton. The average diluted silver grade of both the Indicated Mineral Resources and Inferred Mineral Resources are approximately double that of other past producing or currently producing mines in the Silver Valley.

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Current Sunshine Mine Mineral Resource Estimate (1)(2)(3)(4)(5)(6)(7)(8)(9)(11)(12)

tonne Ag
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| 159.8
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| 776
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(1)

| The effective date of Mineral Resources for the Sunshine Mine is February 24, 2026.
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(2)

| The definitions for Mineral Resources in S-K 1300, which are consistent with the classification scheme under the Committee for Reserves International Reporting Standards, were followed for the classification of Mineral Resources.
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(3)

| All measurements are U.S. standard units or metric units, as indicated.
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(4)

| Mineable stope optimization volume constrained resources with reasonable prospects for economic extraction are stated as contained within vein estimation domains defined by a cut-off grade of 8.8 opt Ag. The cut-off grade and mineable stope optimization are based on the assumed silver price of $23.50 per ounce and operating cost assumptions, as follows: mining cost of $110.00 per ton, processing cost of $20.85 per ton, general and administrative cost of $7.93 per ton, antimony plant for silver concentrate cost of $14.55 per ton, refining for silver concentrate cost of $16.13 per ton and tailings storage cost of $4.27 per ton. See the table under “The Sunshine Complex—Mineral Resource Estimates.”
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(5)

| Mineable stope optimization volumes are 9 feet high, 30 feet long, and minimum of 3 feet wide and are flagged by the individual modeled vein volumes. An unplanned mining dilution of 5% is applied for reporting.
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(6)

| All Mineral Resources are based on a data cut-off date of November 28, 2023, estimated in situ and reported as diluted within mineable stope optimization volume.
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(7)

| Average bulk density was assigned as 3.02 grams per cubic centimeter (g/cm 3 ) for veins and 2.82 g/cm 3 for waste. The equivalent densities in Imperial units are 0.0943 tons per cubic foot (st/ft 3 ) for veins and 0.088 st/ft 3 for waste.
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(8)

| Total metallurgical recovery was assigned at 93% from metallurgical test work and history of mining production.
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| Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. There is no certainty that all or any part of the Mineral Resources will be converted into Mineral Reserves in the future. The estimate of Mineral Resources may be materially affected by environmental permitting, legal, title, taxation, socio-political, marketing or other relevant issues.
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(10)

| Inferred Mineral Resources are considered geologically speculative and are based on limited geological evidence and sampling. High geological uncertainty prevents the application of technical and economic factors to evaluate economic viability.
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(11)

| All quantities are rounded to the appropriate number of significant figures; consequently, sums may not add up due to rounding.
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(12)

| The Sunshine Mine is 100% attributable to SOP (as defined below).
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Select Sunshine Mine Core (2025 /2026 Infill Drill Program)

36 mineralized veins have been discovered at the Sunshine Mine as of February 24, 2026, of which two veins have been identified since we acquired the Sunshine Mine in 2010. Mineralization is comprised of tetrahedrite, freibergite, galena and

TABLE OF CONTENTS
sphalerite, with typical gangue minerals of siderite, quartz, pyrite and magnetite. The silver-bearing mineralization (tetrahedrite) at the Sunshine Mine has also historically contained economic quantities of antimony, as demonstrated by decades of antimony production with concentrate from the Sunshine Mine and other mines. Similar to other vein systems in the Coeur d’Alene Mining District, two main vein assemblages are distinguished, which tend to dominate certain areas of the mine: silver-copper-antimony veins and silver-lead veins. Both tetrahedrite and freibergite form one solid solution series or homogeneous mixture of two compounds that have a single crystal structure. However, the freibergite at the Sunshine Mine has antimony substituted into its chemical structure in a higher frequency compared to arsenic, thus making both tetrahedrite and freibergite a strong source of antimony for the Sunshine Mine. The above core photos are illustrative of the intense mineralized veining consistently observed at the Sunshine Mine.
The Sunshine Technical Report Summary presents the results of an Initial Assessment under two mine operating cases: the Base Case, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, and the Indicated Only Case, which assumes the mining of only Indicated Mineral Resources. Our current evaluation and project planning is based on the Base Case of the Sunshine Technical Report Summary. The Base Case of the Sunshine Technical Report Summary is reflective of our current development strategy to undertake additional infill drilling and other technical work prior to the completion of a Feasibility Study and project sanctioning decision. The Indicated Only Case is shown for illustrative purposes in accordance with Subpart 1302(d)(4) of Regulation S-K.
The Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, envisions an initial 24-year mine life and contemplates producing approximately 6.7 million ounces of payable silver per year on average over the first five years of mine life and approximately 5.8 million ounces of payable silver per year on average over the full 24-year mine life at an all-in sustaining cost (“ AISC ”) (excluding potential copper and lead by-product credits) of $16.26 per ounce of silver produced over the first five years of mine life and $18.81 per ounce of silver produced over the full 24-year mine life. The Indicated Only Case of the Sunshine Technical Report Summary, which assumes the mining of only Indicated Mineral Resources, contemplates producing approximately 3.5 million ounces of payable silver per year on average over the 10-year mine life at an AISC (excluding potential copper and lead by-product credits) of $24.06 per ounce of silver produced over the full 10-year mine life.
Assuming a silver price of $46.36 and operations at full capacity as described in the Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, the Sunshine Mine would generate approximately $311 million in revenue, $230 million in EBITDA and $196 million in operating cash flow on average over the first five years, and approximately $268 million in revenue, $182 million in EBITDA and $153 million in operating cash flow from silver production per year on average over the 24-year mine life. Assuming a silver price of $46.36 and operations at full capacity as described in the Indicated Only Case of the Sunshine Technical Report Summary, the Sunshine Mine would generate approximately $164 million in revenue, $105 million in EBITDA and $97 million in operating cash flow on average over the 10-year mine life.

TABLE OF CONTENTS
Sunshine Technical Report Summary – Initial Assessment (1)(2)

|
|
|
|
|
|
|
Revenue (LOM | Avg. Annual)
|
|
| $6,437M | $268M
|
|
| $1,640M | $164M
|
EBITDA (LOM | Avg. Annual)
|
|
| $4,378M | $182M
|
|
| $1,054M | $105M
|
Operating Cash Flow (LOM | Avg. Annual)
|
|
| $3,681M | $153M
|
|
| $966M | $97M
|
After-tax NPV 5% | IRR
|
|
| $1,434M | 38.3%
|
|
| $270M | 21.1%
|

|
|
|
|
|
|
|

(1)

| Base Case assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources. Indicated Only Case assumes the mining of only Indicated Mineral Resources and is shown for illustrative purposes only in accordance with Subpart 1302(d)(4) of Regulation S-K.
|

(2)

(3)

| Approximately 74% of the tonnage and approximately 68% of the contained silver in the Base Case mine life is Inferred Mineral Resources. Inferred Mineral Resources are considered geologically speculative and are based on limited geological evidence and sampling. High geological uncertainty prevents the application of technical and economic factors that would enable them to be categorized as Mineral Reserves.
|

(4)

| Based on a constant silver price of $46.36/oz Ag in all years of the economic analysis.
|

TABLE OF CONTENTS
Long Section of the Sunshine Mine Core Area & Exploration Target Areas

Within the existing “core” area of the Sunshine Mine (the “ Sunshine Mine Core Area ”), we believe there is significant resource expansion potential in the near-surface or underexplored targets highlighted in yellow coloring above (the “ Upper Country ”), down-dip and horizontal extensions of current veins which are open at depth and underexplored “gaps” in the primary six-mile strike length corridor. This continuity is further highlighted by preliminary results from our recent infill drilling program which has been focused on testing the C-Fault Vein, the South Yankee Boy Vein and the 10 Vein which lie proximal to the Sterling-Polaris-ConSil tunnel. Information set forth herein regarding exploration results from recent infill and exploration drilling, including information relating to drill results, is not contained in the Sunshine Technical Report Summary but accurately reflects findings and conclusions of SRK.

Width (m)
|
|
| Ag (g/t)
|
|
| Cu %
|
|
| Pb %
|
|
| Sb %
|
FS-ST02
|
|
| CFault Vein
|
|
| 140.4
|
|
| 142.0
|
|
| 1.5
|
|
| 2,925
|
|
| 2.75
|
|
| 0.13
|
|
| 1.16
|

|
|
| including
|
|
| 140.8
|
|
| 141.1
|
|
| 0.2
|
|
| 8,880
|
|
| 6.41
|
|
| 0.44
|
|
| 3.39
|
FS-ST03
|
|
| CFault Vein
|
|
| 143.4
|
|
| 144.0
|
|
| 0.6
|
|
| 297
|
|
| 0.23
|
|
| 0.01
|
|
| 0.09
|
FS-ST08
|
|
| CFault Vein
|
|
| 144.3
|
|
| 146.6
|
|
| 2.0
|
|
| 340
|
|
| 0.68
|
|
| 0.31
|
|
| 0.17
|
FS-ST23
|
|
| SYBoy
|
|
| 254.1
|
|
| 254.6
|
|
| 0.3
|
|
| 3,909
|
|
| 1.62
|
|
| 0.16
|
|
| 1.17
|
FS-ST25
|
|
| SYBoy
|
|
| 283.4
|
|
| 283.9
|
|
| 0.4
|
|
| 307
|
|
| 0.10
|
|
| 0.07
|
|
| 0.08
|
FS-ST26
|
|
| CFault Vein
|
|
| 142.5
|
|
| 144.2
|
|
| 1.5
|
|
| 1,076
|
|
| 1.01
|
|
| 0.33
|
|
| 0.43
|
FS-ST26
|
|
| SYBoy
|
|
| 246.1
|
|
| 246.3
|
|
| 0.2
|
|
| 1,954
|
|
| 0.73
|
|
| 0.28
|
|
| 0.57
|
FS-ST26
|
|
| NYBoy
|
|
| 248.2
|
|
| 248.7
|
|
| 0.3
|
|
| 3,607
|
|
| 1.56
|
|
| 0.06
|
|
| 1.18
|

|
|
| including
|
|
| 248.6
|
|
| 248.7
|
|
| 0.1
|
|
| 7,989
|
|
| 3.32
|
|
| 0.07
|
|
| 2.57
|
FS-ST10
|
|
| CFault Vein
|
|
| 188.9
|
|
| 190.0
|
|
| 0.7
|
|
| 3,429
|
|
| 1.17
|
|
| 0.01
|
|
| 0.87
|

|
|
| including
|
|
| 189.7
|
|
| 190.0
|
|
| 0.2
|
|
| 13,783
|
|
| 4.53
|
|
| 0.01
|
|
| 3.46
|
FS-ST11
|
|
| CFault Vein
|
|
| 204.5
|
|
| 205.8
|
|
| 1.1
|
|
| 3,553
|
|
| 1.51
|
|
| 0.00
|
|
| 1.01
|

|
|
| including
|
|
| 205.4
|
|
| 205.6
|
|
| 0.1
|
|
| 23,931
|
|
| 10.40
|
|
| 0.01
|
|
| 6.76
|
FS-ST15
|
|
| CFault Vein
|
|
| 221.1
|
|
| 221.3
|
|
| 0.1
|
|
| 1,341
|
|
| 0.73
|
|
| 0.09
|
|
| 0.48
|
FS-ST18
|
|
| CFault Vein
|
|
| 195.1
|
|
| 195.2
|
|
| 0.1
|
|
| 1,299
|
|
| 0.60
|
|
| 6.79
|
|
| 0.46
|
FS-ST19
|
|
| CFault Vein
|
|
| 219.6
|
|
| 220.9
|
|
| 1.1
|
|
| 453
|
|
| 0.33
|
|
| 1.48
|
|
| 0.17
|
FS-ST21
|
|
| CFault Vein
|
|
| 213.7
|
|
| 214.6
|
|
| 0.7
|
|
| 915
|
|
| 0.38
|
|
| 0.01
|
|
| 0.27
|
FS-ST22
|
|
| SYBoy
|
|
| 245.7
|
|
| 245.8
|
|
| 0.1
|
|
| 4,766
|
|
| 1.71
|
|
| 0.12
|
|
| 1.31
|

|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|

Width (m)
|
|
| Ag (g/t)
|
|
| Cu %
|
|
| Pb %
|
|
| Sb %
|
FS-ST27
|
|
| CFault Vein
|
|
| 143.4
|
|
| 144.9
|
|
| 1.5
|
|
| 340
|
|
| 0.84
|
|
| 0.02
|
|
| 0.16
|
FS-ST27
|
|
| SYBoy
|
|
| 249.3
|
|
| 250.9
|
|
| 1.5
|
|
| 459
|
|
| 0.16
|
|
| 0.09
|
|
| 0.13
|
FS-ST29
|
|
| CFault Vein
|
|
| 215.9
|
|
| 216.3
|
|
| 0.3
|
|
| 9,209
|
|
| 2.82
|
|
| 0.14
|
|
| 2.25
|
FS-ST29
|
|
| SYBoy
|
|
| 233.2
|
|
| 234.2
|
|
| 1.0
|
|
| 439
|
|
| 0.09
|
|
| 1.60
|
|
| 0.08
|
FS-ST30
|
|
| CFault Vein
|
|
| 155.8
|
|
| 156.5
|
|
| 0.7
|
|
| 3,142
|
|
| 1.70
|
|
| 4.32
|
|
| 0.85
|
FS-ST31
|
|
| SYBoy
|
|
| 208.3
|
|
| 209.1
|
|
| 0.7
|
|
| 1,748
|
|
| 0.38
|
|
| 0.03
|
|
| 0.32
|
FS-ST33
|
|
| CFault Vein
|
|
| 174.5
|
|
| 174.7
|
|
| 0.2
|
|
| 651
|
|
| 0.27
|
|
| 6.90
|
|
| 0.20
|
FS-ST34
|
|
| CFault Vein
|
|
| 163.4
|
|
| 164.1
|
|
| 0.6
|
|
| 2,548
|
|
| 1.33
|
|
| 0.06
|
|
| 0.74
|
FS-ST35
|
|
| SYBoy
|
|
| 218.5
|
|
| 220.1
|
|
| 1.5
|
|
| 1,463
|
|
| 0.34
|
|
| 0.45
|
|
| 0.29
|

|
|
| including
|
|
| 219.9
|
|
| 220.1
|
|
| 0.1
|
|
| 7,954
|
|
| 1.65
|
|
| 0.78
|
|
| 1.39
|
FS-ST36
|
|
| CFault Vein
|
|
| 172.1
|
|
| 174.0
|
|
| 1.8
|
|
| 1,976
|
|
| 0.87
|
|
| 0.45
|
|
| 0.55
|

|
|
| including
|
|
| 172.9
|
|
| 173.0
|
|
| 0.1
|
|
| 9,600
|
|
| 3.66
|
|
| 0.01
|
|
| 2.65
|
FS-ST37
|
|
| CFault Vein
|
|
| 183.1
|
|
| 183.2
|
|
| 0.1
|
|
| 1,402
|
|
| 1.16
|
|
| 0.12
|
|
| 0.51
|
FS-ST37
|
|
| SYBoy
|
|
| 220.7
|
|
| 222.0
|
|
| 1.3
|
|
| 939
|
|
| 0.23
|
|
| 0.29
|
|
| 0.20
|

|
|
| including
|
|
| 221.9
|
|
| 222.0
|
|
| 0.1
|
|
| 6,960
|
|
| 1.76
|
|
| 2.28
|
|
| 1.51
|
FS-ST38
|
|
| CFault Vein
|
|
| 211.9
|
|
| 212.5
|
|
| 0.4
|
|
| 3,032
|
|
| 2.24
|
|
| 0.50
|
|
| 1.26
|

|
|
| including
|
|
| 211.9
|
|
| 212.2
|
|
| 0.2
|
|
| 4,149
|
|
| 3.24
|
|
| 0.89
|
|
| 1.70
|
FS-ST39
|
|
| CFault Vein
|
|
| 151.8
|
|
| 151.9
|
|
| 0.1
|
|
| 1,313
|
|
| 1.12
|
|
| 0.16
|
|
| 0.56
|
FS-ST40
|
|
| CFault Vein
|
|
| 144.8
|
|
| 146.0
|
|
| 1.2
|
|
| 3,432
|
|
| 1.68
|
|
| 0.05
|
|
| 1.14
|

|
|
| including
|
|
| 144.8
|
|
| 144.9
|
|
| 0.2
|
|
| 22,560
|
|
| 10.60
|
|
| 0.11
|
|
| 7.46
|
FS-ST40
|
|
| SYboy
|
|
| 205.0
|
|
| 205.1
|
|
| 0.1
|
|
| 6,000
|
|
| 1.51
|
|
| 0.19
|
|
| 1.22
|
FS-ST42
|
|
| SYBoy
|
|
| 226.3
|
|
| 228.1
|
|
| 1.7
|
|
| 3,093
|
|
| 0.76
|
|
| 0.00
|
|
| 0.63
|

|
|
| including
|
|
| 226.3
|
|
| 226.9
|
|
| 0.5
|
|
| 4,423
|
|
| 1.03
|
|
| 0.01
|
|
| 0.91
|

|
|
| including
|
|
| 227.8
|
|
| 228.1
|
|
| 0.2
|
|
| 12,069
|
|
| 3.02
|
|
| 0.01
|
|
| 2.40
|
FS-ST42
|
|
| NYBoy
|
|
| 231.9
|
|
| 232.4
|
|
| 0.5
|
|
| 1,847
|
|
| 0.60
|
|
| 0.06
|
|
| 0.40
|
FS-ST41
|
|
| SYBoy
|
|
| 217.9
|
|
| 218.7
|
|
| 0.7
|
|
| 2,966
|
|
| 0.65
|
|
| 0.37
|
|
| 0.50
|
FS-ST43
|
|
| SYBoy
|
|
| 214.6
|
|
| 214.9
|
|
| 0.3
|
|
| 1,855
|
|
| 0.59
|
|
| 0.18
|
|
| 0.45
|
FS-ST44
|
|
| SYBoy
|
|
| 214.1
|
|
| 217.6
|
|
| 3.4
|
|
| 345
|
|
| 0.10
|
|
| 0.03
|
|
| 0.07
|
FS-ST45
|
|
| SYBoy
|
|
| 222.0
|
|
| 222.2
|
|
| 0.2
|
|
| 651
|
|
| 0.17
|
|
| 0.49
|
|
| 0.14
|
FS-ST46
|
|
| SYBoy
|
|
| 225.1
|
|
| 226.8
|
|
| 1.7
|
|
| 759
|
|
| 0.31
|
|
| 0.08
|
|
| 0.23
|
FS-ST48
|
|
| CFault Vein
|
|
| 216.6
|
|
| 216.9
|
|
| 0.3
|
|
| 2,136
|
|
| 1.62
|
|
| 0.03
|
|
| 0.84
|
FS-ST50
|
|
| TBD
|
|
| 224.0
|
|
| 224.8
|
|
| 0.4
|
|
| 460
|
|
| 0.22
|
|
| 0.03
|
|
| 0.17
|
FS-ST51
|
|
| 10Vein
|
|
| 122.7
|
|
| 123.3
|
|
| 0.4
|
|
| 12,240
|
|
| 3.67
|
|
| 0.56
|
|
| 2.48
|
FS-ST53
|
|
| NYBoy
|
|
| 281.0
|
|
| 281.6
|
|
| 0.5
|
|
| 562
|
|
| 0.29
|
|
| 0.20
|
|
| 0.23
|
FS-ST60
|
|
| 10Vein
|
|
| 104.3
|
|
| 112.5
|
|
| 5.3
|
|
| 566
|
|
| 0.25
|
|
| 4.51
|
|
| 0.19
|

|
|
| including
|
|
| 105.0
|
|
| 106.7
|
|
| 1.1
|
|
| 1,969
|
|
| 0.87
|
|
| 11.91
|
|
| 0.67
|
FS-ST61
|
|
| 10Vein
|
|
| 124.7
|
|
| 132.3
|
|
| 3.8
|
|
| 518
|
|
| 0.11
|
|
| 10.98
|
|
| 0.11
|
FS-ST62
|
|
| 10Vein
|
|
| 103.0
|
|
| 105.6
|
|
| 1.3
|
|
| 332
|
|
| 0.02
|
|
| 14.12
|
|
| 0.04
|
FS-ST63
|
|
| 10Vein
|
|
| 66.8
|
|
| 67.1
|
|
| 0.2
|
|
| 1,083
|
|
| 0.20
|
|
| 24.40
|
|
| 0.20
|
FS-ST64
|
|
| New
|
|
| 178.5
|
|
| 179.6
|
|
| 1.1
|
|
| 319
|
|
| 0.21
|
|
| 1.01
|
|
| 0.16
|
FS-ST64
|
|
| 10Vein
|
|
| 183.6
|
|
| 184.3
|
|
| 0.6
|
|
| 403
|
|
| 0.02
|
|
| 15.63
|
|
| 0.05
|
FS-ST65
|
|
| 10Vein
|
|
| 97.7
|
|
| 98.6
|
|
| 0.6
|
|
| 193
|
|
| 0.10
|
|
| 0.33
|
|
| 0.07
|
FS-ST66
|
|
| 10Vein
|
|
| 139.5
|
|
| 140.7
|
|
| 0.9
|
|
| 684
|
|
| 0.02
|
|
| 23.12
|
|
| 0.08
|
FS-ST67
|
|
| 10Vein
|
|
| 139.0
|
|
| 139.8
|
|
| 0.8
|
|
| 1,173
|
|
| 0.11
|
|
| 42.40
|
|
| 0.17
|
FS-ST69
|
|
| 10Vein
|
|
| 123.2
|
|
| 123.9
|
|
| 0.5
|
|
| 1,894
|
|
| 0.73
|
|
| 26.37
|
|
| 0.59
|
FS-ST69
|
|
| SYBoy
|
|
| 203.2
|
|
| 203.6
|
|
| 0.3
|
|
| 617
|
|
| 0.19
|
|
| 0.08
|
|
| 0.16
|
31-2501
|
|
| New
|
|
| 127.9
|
|
| 129.4
|
|
| 1.2
|
|
| 2,359
|
|
| 0.60
|
|
| 0.02
|
|
| 0.54
|
31-2501
|
|
| New
|
|
| 134.1
|
|
| 134.2
|
|
| 0.1
|
|
| 1,104
|
|
| 0.34
|
|
| 0.09
|
|
| 0.28
|
FS-ST58
|
|
| 10Vein
|
|
| 138.8
|
|
| 139.8
|
|
| 0.3
|
|
| 959
|
|
| 0.10
|
|
| 32.35
|
|
| 0.14
|
FS-ST58
|
|
| NYBoy
|
|
| 226.6
|
|
| 228.1
|
|
| 1.1
|
|
| 237
|
|
| 0.05
|
|
| 0.04
|
|
| 0.05
|

|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|

Width (m)
|
|
| Ag (g/t)
|
|
| Cu %
|
|
| Pb %
|
|
| Sb %
|
FS-ST59
|
|
| 10Vein
|
|
| 118.3
|
|
| 118.5
|
|
| 0.1
|
|
| 861
|
|
| 0.29
|
|
| 6.79
|
|
| 0.23
|
FS-ST59
|
|
| NYBoy
|
|
| 218.9
|
|
| 219.1
|
|
| 0.1
|
|
| 758
|
|
| 0.04
|
|
| 23.10
|
|
| 0.11
|
FS-ST59
|
|
| SYBoy
|
|
| 221.3
|
|
| 222.6
|
|
| 1.0
|
|
| 681
|
|
| 0.14
|
|
| 0.09
|
|
| 0.13
|
FS-ST71
|
|
| 10Vein
|
|
| 140.8
|
|
| 140.9
|
|
| 0.1
|
|
| 32,331
|
|
| 16.50
|
|
| 12.80
|
|
| 11.10
|
FS-ST71-A
|
|
| 10Vein
|
|
| 140.3
|
|
| 140.5
|
|
| 0.2
|
|
| 5,417
|
|
| 2.73
|
|
| 0.41
|
|
| 2.08
|

|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|

Beyond the Sunshine Mine Core Area, we believe there is significant opportunity for new discovery across our highly prospective, underexplored and newly consolidated district-scale land package in the Silver Valley, which has seen little modern-day exploration. In 2024, we engaged Scout to evaluate the exploration potential of our broader land package and to develop a systematic district-scale exploration roadmap. Scout’s work included a 2024 desktop review of historic exploration data followed by a 2025 reconnaissance fieldwork program comprising geologic observations and geochemical sampling across the South Sunshine, Pine Creek and Rock Creek areas of our land package, including 322 man-days of field work, 128 rock samples and 2,935 soil samples. Overall results of this program include the identification of drill-ready targets at the Pine Creek and Rock Creek areas. Scout is an affiliate of the Company. See “ Qualified Persons Statement .”

Silver Industry Overview
Metal Overview
Silver is a precious metal occurring naturally in its solid metallic state and is commonly associated with deposits of gold, copper, lead and zinc. It is widely used in both industrial applications and as an investment asset. Unlike many other commonly mined major metals, approximately 74% of mined silver supply is delivered as a by-product from the mining of other metals. This makes primary silver deposits of scale, like the Sunshine Mine, rare.
Silver’s distinct physical and chemical properties drive diversified and growing industrial demand for silver, including from applications in artificial intelligence (“ AI ”). Silver is the best metallic conductor of electricity, and its sensitivity to and high reflectance of light, along with its strength and ability to withstand extreme temperature changes, restrict silver’s substitution in most applications.
Silver has also been used throughout much of human history as a store of value. As an investment asset, silver is viewed as an attractive hedge against inflation or devaluation of fiat currencies, and as a risk-off asset during times of economic or geopolitical uncertainty.
Demand Side
Industrial demand accounted for approximately 58% of total silver demand in 2025, according to the Silver Institute’s “World Silver Survey 2026” report. Industrial demand for silver is expected to increase by 17% by 2032 over 2026 levels, according to the “Silver 10-Year Projections” report published by CPM Group in June 2025 (the “ CPM Silver Data Report ”).

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Silver is essential in solar panels, superconductors and personal electronics due to its conductivity and temperature-resistance. Photovoltaic cells rely on silver to optimize energy output, while electric vehicles use silver in sensors, wiring and control modules. Silver is also used in energy storage.
Demand for silver from solar applications has accelerated in recent years, given solar’s key role in the transition to green energy. Additionally, increased volatility in the global energy markets due to armed conflicts and geopolitical uncertainty have historically driven up demand for alternative energy sources, such as solar, that are less vulnerable to global supply chain disruptions. As a result, we believe current energy security dynamics may accelerate demand for silver. We expect other emergent themes, including AI, nano silver, biocides and other applications to continue driving industrial demand growth for silver.
Silver is an essential component used in technology driving the energy transition and in most consumer electronics. Silver’s diversified industrial uses contribute to demand resilience, and because most applications require only small quantities of metal, substitution is limited and industrial demand has historically been relatively price inelastic.
Forecast Industrial Demand for Silver

Source: CPM Silver Data Report
Silver has also served as a safe haven asset, a portfolio diversifier and a form of currency with no default risk for approximately 4,000 years. We expect investment demand for silver to continue rising, as it has historically grown during periods of sustained geopolitical, macroeconomic and financial risks, and devaluation of fiat currencies. 2025 demonstrated silver’s utility as an investment asset, with signs of increasing institutional demand. Against the current geopolitical and macroeconomic backdrop, and given the under-ownership of silver in current institutional portfolios relative to gold and other real assets, we believe there is substantial runway for investment demand growth.
Supply Side
Silver supply is largely driven by mined silver production, which accounted for approximately 78% of total silver supply in 2025. Mined supply is sourced primarily from Mexico, China and Peru, which collectively accounted for approximately 49% of global mined supply in 2025, compared to only approximately 4% from the United States. China, the world’s third-largest silver producer in 2025, added silver to its critical minerals list and introduced new regulations in October 2025 establishing qualification and review requirements for enterprises exporting silver during 2026 and 2027, reflecting heightened government oversight of silver exports from a major producing jurisdiction. While the ultimate impact of this policy on global silver supply and pricing remains uncertain, any restrictions or delays in exports from China (which accounted for approximately 13% of silver supply in 2025) could further constrain global silver availability.
Mined supply has been in a declining trend since 2016 due to reserve depletion, declining ore grades, limited new discoveries and a long period of under-investment in new capacity. Annual additions to silver mining capacity in near-term mine development projects fell 80% between 2013 and 2024, and only approximately 26% of global mined supply in 2025 came from primary silver mines. Due to the by-product nature of most mined silver, project sanctioning decisions that would increase silver supply often depend on the economics of other metals being mined, instead of the underlying fundamentals of the silver market, thereby reducing supply-side response to growing silver demand.
Pricing and Outlook
The silver market remains in a supply deficit. This dynamic creates a highly supportive structural backdrop for spot silver prices and an attractive opportunity for silver explorers and producers.
Silver prices rose sharply in 2025, from $29.56 per ounce on January 2, 2025 to approximately $72.15 per ounce on December 31, 2025, representing an increase of approximately 144%, and have remained strong in 2026. The current

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spot price of silver was $81.13 per ounce as of May 8, 2026, as per APMEX. The silver supply deficit, combined with macroeconomic factors such as declining interest rates, inflation, geopolitical uncertainty and devaluation of fiat currencies, provides additional tailwinds for potential further price appreciation. While higher silver prices can positively affect the economics of silver exploration and development projects, silver prices are volatile and subject to significant fluctuations based on macroeconomic, monetary and geopolitical factors.
Antimony Industry Overview
Antimony is recognized as a critical mineral in the United States, European Union (“ EU ”), Japan and Australia. Its unique chemistry makes it essential in defense and several civilian supply chains. As of 2024, China accounted for 43% of global antimony mine production and hosted 90% of the world’s antimony smelting capacity, according to the Argus Report. In response to China’s export controls and escalating geopolitical tensions, there is increased interest in developing domestic supply chains for antimony in the United States and Europe. Elevated antimony prices outside of China and domestic protectionist policies in the United States and Europe are expected to create significant opportunity for domestic antimony suppliers, underscoring both the strong strategic and industrial logic behind the potential development of the Sunshine Antimony Plant.
Metal Overview
Antimony is a brittle, silvery metalloid mainly found in the form of stibnite. Most current production of antimony comes from quartz-stibnite veins and replacement deposits, with antimony extracted both as a primary product and as a by-product of mining operations. Antimony trisulfide is commonly used in military applications such as ammunition and explosives, as well as in flame retardants and semiconductors. The U.S. Army aims to establish a “ground-to-round” domestic supply chain for antimony trisulfide. According to the Argus Report, more than 300 types of munitions rely on this compound.
Demand Side
Global Antimony Demand by End Use (tonnes)

Source: Argus Report
According to the Argus Report, 45% of global antimony demand in 2024 was driven by the use of antimony as a flame retardant in construction materials, plastics, textiles and electrical or electronic components, including for wiring in data centers. In defense applications, antimony-based flame retardants are built into uniforms, vehicle interiors, cables and components where fire resistance is a mission-critical safety requirement. An additional 23% of global antimony demand in 2024 was for metallurgical alloys (with wide-ranging applications from their use in lead-acid batteries to increasing hardness in ammunition) and an additional 16% of antimony demand in 2024 was driven by solar glass and ceramics (driven by ongoing expansion in the solar photovoltaic sector in recent years). Antimony is also used in semiconductor doping, compound semiconductors, energy storage and polyester catalysts, among other applications.
Global antimony demand is expected to increase by 35% from 170 kilotonnes in 2024 to approximately 230 kilotonnes by 2040 according to the Argus Report. The United States is a major consumer, mainly importing antimony oxides. U.S. net imports of antimony oxides have risen sharply in recent years. A growing area of demand in the United States is expected to come from data centers being built for the growth in AI technology as wiring systems for these applications require flame retardants.

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According to the Argus Report, mature, industrial applications are expected to sustain current demand for antimony, but technological innovation in photovoltaics and battery chemistries, growing data center capacity, as well as expanding military budgets, are expected to drive future demand growth.
Supply Side
China, Myanmar, Tajikistan and Russia accounted for 81% of global antimony mine production in 2024, with China accounting for 43% of global antimony mine production and hosting 90% of the world’s antimony smelting capacity, according to the Argus Report. With this market structure, global antimony supply is characterized by persistent tightness and volatility, driven by resource depletion in major producing countries, Chinese export controls and geopolitical factors. Production has lagged demand in recent years, and this supply deficit is expected to continue in coming years for U.S. and Western importers if Chinese supply restrictions persist and additional ex-China capacity from new projects is not added.
China implemented export restrictions on antimony in September 2024, requiring companies to obtain export licenses from the commerce ministry. These controls were expanded in December 2024 to include an outright ban on exporting “dual-use” items like antimony to U.S. military users or for military purposes. On November 9, 2025, China suspended its U.S. export ban on antimony. However, Chinese antimony exports remain subject to dual-use controls and U.S. importers still need to navigate China’s export licensing system, which is considered a significant regulatory hurdle. These restrictions and, more broadly, sustained geopolitical tensions, have catalyzed U.S. and Western efforts towards diversification and re-shoring of critical mineral supply chains.
While the United States has antimony reserves, no mines have been active since 1992, and the country relies heavily on imports. U.S. Antimony Corporation (“ USAC ”) is the only significant operating processor of antimony products in the United States, and according to USAC’s company filings, it currently supplies approximately 4% of U.S. demand for antimony oxide products. USAC is reopening a mine in Montana and has leased mineral rights in Alaska, while Perpetua Resources Corp. is developing the Stibnite gold-antimony project in Idaho. The U.S. government has been highly supportive of domestic antimony production efforts, and we expect it to remain so in the foreseeable future.
We are progressing design and planning for the Sunshine Antimony Plant with a potential nameplate annual capacity of up to 34.5 million pounds (15.6 kilotonnes) of finished antimony. Based on forecasts of global antimony demand from the Argus Report and assuming U.S. demand growth matches global demand growth, we believe U.S. demand for antimony will be approximately 59 million pounds by 2030. If the contemplated nameplate annual capacity of 34.5 million pounds (15.6 kilotonnes) is achieved, the Sunshine Antimony Plant could supply up to 60% of U.S. demand using antimony-bearing concentrate from the Sunshine Mine, as well as from third party sources. We believe we are strategically well-positioned to supply the U.S. market.
Pricing and Outlook
In 2024 and 2025, Chinese export controls led to a surge in antimony prices outside China. U.S. and European antimony metal prices increased by approximately 350% between April 2024 and June 2025, when prices peaked just above $60,550 per tonne in the United States and $60,700 per tonne in Europe. Despite moderating in the second half of 2025, antimony prices in the United States and Europe remain meaningfully higher than historical levels.
Antimony prices outside China are expected to remain elevated due to tightening supply and rising strategic demand, according to the Argus Report, which projects that U.S. antimony prices will reach $48,000 per tonne in 2030 and $60,500 per tonne in 2040, representing a significant premium over historically prevailing prices.

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U.S. Antimony Price Forecast

(Antimony min 99.65% CIF US) ($ per tonne)

Source: Argus Report
We believe domestic production from Idaho will benefit from this strong price environment and command a strong premium over Chinese production, especially in guaranteed long-term offtake contracts with defense, critical infrastructure and potentially original equipment manufacturer customers in the United States. According to the base case of the Argus Report, antimony prices in Europe are expected to maintain their current levels in 2026 (approximately $40,000 per tonne) and then match the China price forecast at a 75% premium, while U.S. prices are projected to hold a 2% premium over Europe.
We believe long-term market structure and geopolitical trends have converged to create a conducive environment for the potential antimony restart project at the Sunshine Complex, affording us strong prospects for attractive long-term pricing, contracted offtake and upside optionality if export controls tighten further. We believe antimony has transitioned from a niche minor metal to a strategic specialty where credible U.S. producers can expect durable pricing power while addressing a key strategic security need.
Business Strengths and Competitive Advantages
Highly experienced management team and Board of Directors
We have an experienced management team with a track record of successfully identifying and developing mineral discoveries. Our management team possesses deep experience in the Silver Valley, and demonstrated capabilities across mine development and operations, engineering and safety and permitting and land management. See “ Management .”
The Company is led by Heather White, our Chief Executive Officer, who is a recognized leader in the global mining industry with a proven track record of achievements. Ms. White is a seasoned mining engineer, developer, operator and executive with 30 years of experience. She has held senior management roles at mining companies such as Inco Limited, Voisey’s Bay mine, Vale S.A., NOVAGOLD Resources Inc. and Nickel Creek Platinum Corp.
André van Niekerk, our Chief Financial Officer, is an accomplished corporate officer with more than 25 years of mining industry experience in financial strategy, capital markets, corporate governance and operational excellence. Mr. van Niekerk previously served as Chief Financial Officer of Gatos Silver, Nevada Copper Corp. and Golden Star Resources Ltd.
Michelle Shepston, our General Counsel and Secretary, is an experienced executive with over 25 years of expertise in corporate and securities law, mergers and acquisitions, equity and debt transactions, compliance, risk management and corporate governance. Ms. Shepston previously served as an executive vice president and general counsel and secretary of Hoonigan and DMC Global Inc.
Tom Henderson, our General Manager, is a mining engineer with more than 40 years of experience in underground and open-pit mining, including roles ranging from miner to Chief Operating Officer. Mr. Henderson has developed and operated mines in the United States (Idaho, Nevada and Alaska) as well as globally. Mr. Henderson has previously held positions in several mines in the Silver Valley, along with numerous outside projects including at the Grasberg, Goldstrike and Kensington mines.
Nick Furlin, our Technical Services Manager, is an experienced geologist and technical services management professional with 20 years of experience working in the Silver Valley, including 16 years at Hecla’s Lucky Friday mine.

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Mr. Furlin helped develop the revolutionary “Underhand Closed Bench” mining method, which is a specialized underground mining technique used to improve safety and productivity compared to conventional techniques.
Our Board of Directors also comprises senior mining and financial executives with career backgrounds at notable mining companies and global experience in mineral exploration, development and mining. See “ Management .”
We believe that the specialized skills and knowledge of our management team and Board of Directors enhance our ability to create value from the restart of the Sunshine Mine and through other opportunities, such as antimony processing on-site and exploration of our highly prospective, newly consolidated, district-scale land package around the Sunshine Mine.
The Sunshine Mine is one of the highest grade primary silver deposits globally, with average diluted silver grades approximately double that of other past producing or currently producing mines in the Silver Valley
The Sunshine Mine is one of the highest-grade primary silver deposits worldwide. As of February 24, 2026, known resources at the Sunshine Mine include Indicated Mineral Resources of 3.5 million tons in mineralized material at an average diluted silver grade of 29.8 ounces per ton, containing 103.9 million ounces of silver, and Inferred Mineral Resources of 7.1 million tons in mineralized material at an average diluted silver grade of 22.6 ounces per ton, containing 159.8 million ounces of silver. Our resources are reported after factoring in mining dilution, meaning the grade of silver is representative of the estimated grade of material that will enter our milling facility.
A high concentration of silver signifies that more metal can be produced for every tonne of mineralized material mined and processed, which results in lower costs and higher margins.
The geological formation that hosts our silver resources is similar to that of other nearby deposits and operations in the Silver Valley. Our silver-bearing veins are of similar width to other operating assets in the Silver Valley with the same ore bearing minerology, but the average diluted silver grade of both the Indicated Mineral Resources and Inferred Mineral Resources at the Sunshine Mine are approximately double that of other past producing or currently producing mines in the Silver Valley.

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Global High-Grade Silver Assets – Average Diluted Silver Grade of Measured Mineral Resources &

Indicated Mineral Resources (grams per tonne ) (1)(2)(3)

Global High-Grade Silver Assets – Average Diluted Silver Grade of Inferred Mineral Resources (grams per tonne ) (1)(2)

(1)

| Source: Company Filings.
|

(2)

| Top 15 highest grade active primary silver assets globally excluding Russia. Includes projects with contained Measured Mineral Resources and Indicated Mineral Resources of at least 45 million ounces of silver and contained Inferred Mineral Resources of at least 5 million ounces of silver.
|

(3)

| Measured Mineral Resources and Indicated Mineral Resources are inclusive of Mineral Reserves where applicable. Shown on a silver basis only (only illustrates silver grams per tonne of mineralized material, or ore, where applicable; excludes other commodities that also may be present).
|

Large-scale, long-life silver production plan with attractive cost profile providing strong exposure to the compelling silver market backdrop
The Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, contemplates producing approximately 6.7 million ounces of payable silver per year on average over the first five years of mine life and approximately 5.8 million ounces of payable silver per year on average over the full 24-year mine life, which would make it the second largest primary silver mine in the United States and would represent roughly 16% of the 35.7 million ounces of silver produced in the United States during 2025, according to the Silver Institute’s “World Silver Survey 2026” report. The Indicated Only Case of the Sunshine Technical Report Summary contemplates producing approximately 3.5 million ounces of payable silver per year on average over the 10-year mine life. Based on the Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, AISC is expected to average $18.81 per ounce of silver produced (excluding potential copper and lead by-product credits), significantly below the current spot price of silver ($81.13 per ounce as of May 8, 2026, as per APMEX) and in the second-lowest quartile of

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global assets with silver production co-product AISC curve. Based on the Indicated Only Case of the Sunshine Technical Report Summary, which assumes the mining of only Indicated Mineral Resources, AISC is expected to average $24.06 per ounce of silver produced (excluding potential copper and lead by-product credits).
Current Co-Product Silver AISC Cost Curve ($/oz Ag Co-Product) (1)(2)(3)(4)

(1)

| Source: S&P Capital IQ Pro.
|

(2)

| Based on global (excluding Russia) 2024 actual cost curve as provided by S&P Global.
|

(3)

| Includes all mines with reported silver production in the calendar year 2024, excluding operations with less than 500,000 ounces of silver production.
|

(4)

| Figures are displayed on a co-product basis and are calculated by S&P Global in which costs are shared according to revenue value splits of the metals in each product.
|

We have strong leverage to silver: the Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, estimates the after-tax net present value (“ NPV ”) of the Sunshine Mine to be $1.4 billion, based solely on silver revenues, assuming a $46.36 per ounce silver price and a 5% discount rate, the prevailing industry standard discount rate for evaluating precious metals projects in North America. According to the Sunshine Technical Report Summary, increasing the assumed silver price to $60.27 per ounce and $80.00 per ounce would increase the after-tax NPV to $2.2 billion and $3.2 billion, respectively, in the Base Case, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources. The Indicated Only Case of the Sunshine Technical Report Summary, which assumes the mining of only Indicated Mineral Resources, estimates the after-tax NPV of the Sunshine Mine to be $270 million, based solely on silver revenues, assuming a $46.36 per ounce silver price and a 5% discount rate, the prevailing industry standard discount rate for evaluating precious metals projects in North America. These after-tax NPVs do not account for potential contributions from copper and lead, as well as antimony and other critical minerals, or any potential resource expansion resulting from additional exploration. Additionally, we do not currently have any commodity hedging, offtake agreements or debt in place that would limit economic exposure of the Sunshine Mine to the attractive silver market.

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After-Tax Sensitivity Analysis – Sunshine Technical Report Summary

|
|
|
|
|
|
|

|
|
| Base Case (1)(2)
|
|
| Indicated Only Case (1)
|
Variance
|
|
| Silver Price
|
|
| NPV5%
|
|
| IRR
|
|
| Silver Price
|
|
| NPV5%
|
|
| IRR
|
(%)
|
|
| ($/oz)
|
|
| ($ in

millions)
|
|
| (%)
|
|
| ($/oz)
|
|
| ($ in

millions)
|
|
| (%)
|
100%
|
|
| $46.36
|
|
| $1,434
|
|
| 38.3%
|
|
| $46.36
|
|
| $270
|
|
| 21.1%
|
130%
|
|
| $60.27
|
|
| $2,173
|
|
| 49.0%
|
|
| $60.27
|
|
| $524
|
|
| 31.7%
|
173%
|
|
| $80.00
|
|
| $3,220
|
|
| 61.5%
|
|
| $80.00
|
|
| $878
|
|
| 43.2%
|

|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|

(1)

(2)

We believe the strong fundamentals of the Sunshine Mine provide scaled, long-term exposure at an attractive cost structure to a robust silver market that is benefiting from resilient and secular trends. Industrial demand for silver as a critical mineral with key applications in photovoltaics, energy storage and electronics continues to increase, while investment demand for silver as a store of value is also beginning to accelerate. Despite robust and growing industrial and investment demand, the supply side remains constrained and in persistent deficit.
Existing underground and surface infrastructure allows rapid return to operations and low capital costs
The Sunshine Complex has well-established infrastructure in place. We estimate that it would currently cost approximately $600 million to replace this existing infrastructure (which includes shaft and adit access to the deposit, mobile underground equipment and various components of surface infrastructure related to mineral processing and tailings disposal), and we also believe it could take several years to obtain the requisite permits. Since the Sunshine Complex was acquired by Electrum in 2010, approximately $208 million has been invested to consolidate, maintain in good-standing and modernize it in preparation for restarting operations. This included dewatering, redevelopment of the existing underground works with ventilation infrastructure, upgrades to and acquisition of mobile underground mining equipment, as well as the Sunshine Tailings Storage Facility. This installed asset base provides us with a significant head start in restarting operations and materially reduces the amount of capital required for us to achieve production relative to a new project without existing infrastructure. As a result, our capital intensity, representing the investment required per ounce of new silver production, compares favorably relative to other large scale silver projects.
Potential to become a major integrated antimony and critical mineral mining and refining hub in the United States
Antimony is a critical mineral required for the national security of the United States. Antimony has many end-use applications with national security relevance including munitions production, flame retardants, batteries and semiconductors. Today, the U.S. supply of upstream and processed antimony is heavily dependent on imports, much of which have historically originated from China, Russia and Tajikistan. In August 2023, China, the world’s largest producer of antimony, announced export restrictions on antimony, and an export ban to the United States went into effect in December 2024. U.S. antimony prices rose from approximately $12,948 per ton in January 2024 to $44,800 per ton in November 2025 according to the Argus Report. In November 2025, China paused its ban on exports of gallium, germanium and antimony and related end-use items to the United States until November 2026. Although this represents a de-escalation of trade tensions between the two countries, the three metals are still subject to broader export controls requiring licenses from the Chinese government, and uncertainty remains for future supply disruptions.
Recent geopolitical tensions have highlighted China’s dominance in the production and refining of antimony and other critical minerals. To reduce this strategic imbalance and dependence on foreign supply chains, the U.S. government has announced several initiatives to secure and strengthen domestic supply of critical minerals. Between July 2025 and November 2025, the U.S. government publicly announced approximately $6 billion of direct and indirect investments of both equity and debt into U.S. mineral projects.
We believe a restart of mining/milling operations at the Sunshine Complex and developing the Sunshine Antimony Plant, along with refurbishing, constructing and restarting the Sunshine Silver/Copper Refinery, can significantly help address the U.S. supply chain gap for antimony and potentially other critical minerals including gallium and

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germanium. We are progressing design and planning for the development of the Sunshine Antimony Plant with a potential nameplate annual capacity of up to 34.5 million pounds of finished antimony. Based on forecasts of global antimony demand from the Argus Report and assuming U.S. demand growth matches global demand growth, we believe U.S. demand for antimony will be approximately 59 million pounds by 2030. If the contemplated nameplate annual capacity of 34.5 million pounds is achieved, the Sunshine Antimony Plant could supply up to 60% of U.S. demand using antimony-bearing concentrate from the Sunshine Mine, as well as from third party sources. Any ability to sell antimony by-product and process third-party antimony feed would generate additional revenue.
The historic Sunshine Mine was a primary producer of antimony in the United States between 1953 and 2001, and we have maintained all major permits required to develop an antimony refinery on site. These existing permits enable the development of the Sunshine Antimony Plant with the ability to process antimony-bearing concentrate from the Sunshine Mine and from other third-party mines in the United States, thereby potentially delivering one of the only critical mineral mining and refining hubs of scale in the United States.
In 2025, Samuel Engineering completed a Class 5 Study for the Sunshine Antimony Plant which evaluated a plant with the annual capacity to produce up to 34.5 million pounds of antimony, based on 100 tons per day of antimony concentrate, at an estimated capital cost of approximately $150 million. We are undertaking a Feasibility Study for the development of the Sunshine Antimony Plant as part of our technical evaluation ahead of a potential decision to pursue the development of the Sunshine Antimony Plant and, in parallel with the Feasibility Study and based on the results of the Feasibility Study, we may evaluate external financing alternatives and strategic transactions with respect to the Sunshine Antimony Plant.
The existence of antimony at the Sunshine Mine (as demonstrated by decades of historical mining), in addition to our permitted status for a future antimony refinery of scale with the ability to process third-party antimony feed, differentiates us from other antimony producers, and we may also be able to process other critical minerals such as germanium and gallium in the future. Permitting represents a key constraint for similar developments in the United States and peer nations, giving us an advantage in potential downstream diversification.
To further expand our potential capacity to refine critical minerals at the Sunshine Complex, we are investigating and testing methods to extract additional critical minerals, such as germanium and gallium, both of which were historically present in ore from the Sunshine Mine. Assays of recent drill intercepts and tailings samples have shown meaningful quantities of germanium and gallium, as well as other critical minerals. If an adequate method is found to deliver cost-efficient extraction and purification of these critical minerals, we may integrate the requisite technology into the refining operations we are developing, with the potential to generate additional revenue from such critical minerals. However, SLR and SRK have not estimated antimony, copper, lead, gallium or germanium Mineral Reserves or Mineral Resources, and we may not be able to demonstrate reasonable prospects for economic extraction of these by-products or other critical minerals. See “ Risk Factors—Risks Related to Our Business and Industry—We are dependent on the Sunshine Mine for our future operations. The Sunshine Mine does not currently have any Proven Mineral Reserves or Probable Mineral Reserves, or any antimony, copper, lead, gallium or germanium reserves or resources, as defined under S-K 1300. ”
Near-mine and district-wide exploration targets provide opportunities for significant resource discovery and growth beyond existing mine plan
Within the Sunshine Mine Core Area, we see significant resource expansion potential in the Upper Country, including down-dip and horizontal extensions of current veins which are open at depth and underexplored “gaps” in the primary six-mile strike length corridor. The Sunshine Mine has several underexplored veins in the Sunshine Mine Core Area, each of which holds the potential to be as prolific as the historic Sunshine Vein and Chester Vein, each of which is reported to have produced over 90 million ounces of silver while in production according to the Sunshine Technical Report Summary. Within our core land package, the existing mineralization system is open along strike eastward and at depth.
We believe the defined, near-surface veins of the Upper Country, along with other areas that have not yet been explored or tested, offer the potential to support expanded Mineral Resources, annual production and a longer mine life. The historic discovery and development of high-grade veins at depth diverted attention from the Upper Country and other areas surrounding the Sunshine Mine, leaving large gaps of underexplored ground. Vein systems in the Coeur d’Alene Mining District typically produce a series of parallel veins, many of which, in the Upper Country, have not been defined but have been previously identified, suggesting the potential to discover and define additional veins.

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Ongoing exploration work suggests additional resource potential beyond the current Indicated Mineral Resources and Inferred Mineral Resources in our highly prospective, newly consolidated, district-scale land package around the Sunshine Mine. Since 2010, we have expanded our land position from 2,400 hectares to 9,561 hectares. Consolidated ownership and control of this highly prolific district provides us with exceptional blue-sky exploration upside.
In March 2026, Scout prepared an exploration roadmap for our land package based on review of historical data followed by reconnaissance field work, geologic observations and geochemical sampling. Scout’s recommended next steps contemplate detailed mapping and systematic soil geochemistry along with an initial 15,000-meter surface drilling program targeting high priority areas of our land package. We believe this roadmap provides a disciplined framework to prioritize capital toward high priority targets to support potential Mineral Resource growth. According to Scout, the combination of historic production, extensive vein development and limited on-strike testing through March 2026 indicates that substantial discovery potential remains for new silver, base metals and antimony, both adjacent to and beyond known mineralization.
We believe the exploration targets near the Sunshine Mine and across the broader land package could materially increase our Mineral Resource base, extend our mine life and expand annual production. Accordingly, we intend to explore the Upper Country and other areas surrounding the Sunshine Mine with a sustained exploration program deploying multiple drill rigs.
Geopolitically safe and attractive, established mining region
The Sunshine Complex is located in the Silver Valley in Idaho in the United States. The United States is broadly recognized as a geopolitically stable and safe jurisdiction with a strong rule of law, and Idaho is a mining-friendly region, with a long history of successful mineral development and operations.
As widely reported, there has been an increase in resource nationalism globally. With rising demand for precious metals and critical minerals, governments in certain regions have tightened control over, and fiscal take from, mining assets. We believe resource nationalism will continue, enhancing the relative attractiveness of investments in precious metals and critical minerals producers and developers in high quality jurisdictions, like the United States, which offer regulatory stability, respect for property rights, transparent governance and predictable legal and fiscal frameworks.
Based on the Fraser Institute’s 2025 survey of global mining and exploration companies ranking jurisdictions to the extent public policy factors encourage or are not a deterrent to mining investment, Idaho ranks amongst the top ten most attractive jurisdictions for mining investment in the United States, and, on a global basis, amongst the top ten based on taxation regime, socioeconomic agreements/community development conditions, and labor regulations. The mining industry in the Silver Valley also enjoys strong local and state government support and benefits from significant local community involvement and compelling geological prospectivity. With its history as one of America’s most prolific silver districts, the Sunshine Complex’s attractive location within the Silver Valley affords it access to strong infrastructure, such as low-cost hydroelectric power, road, rail and airport logistics, as well as an experienced local labor force.
Demonstrated environmental track record and stated objective to prioritize community empowerment and responsible development
We integrate innovative technology, safety, environmental care and strong community partnerships into every aspect of our operations. We have a long record of compliance with applicable environmental laws and permits. Investments in zero-liquid-discharge water technology, tailings rehabilitation and modernized environmental systems reflect a proactive approach to sustainability and the protection of the Idaho Silver Belt. We are currently in partnership with the Bureau of Land Management and the U.S. Forest Service on habitat restoration, campground clean-ups and debris removal from streams. We also possess the major permits required to restart mining, milling and refining operations including a multi-sector general permit, an Idaho Pollutant Discharge Elimination System (“ IPDES ”) permit and a certificate of approval for the Sunshine Tailings Storage Facility, and we will not require an environmental impact study to initiate restart of such operations. We do not anticipate issues in maintaining our current permitting status or securing the outstanding and ongoing permits required. A summary of relevant permits and their status is included in Table 17-1 of the Sunshine Technical Report Summary. Our current permits will be subject to normal course updates throughout the construction process.
Our community engagement plan includes local residents, indigenous communities and the state government to streamline the development process. The Silver Valley is known for favorable and stable mining regulations, with a history of over 140 years of mining. The Silver Valley also provides a ready source of skilled and unskilled labor. Efforts

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are made to stimulate the local economies as much as possible, with the area having numerous vendors that supply services to the mining industry. Additionally, our team enjoys a positive relationship with the Coeur d’Alene Tribe, which has a long history of mining connectivity and has co-sponsored several restoration projects in the Coeur d’Alene Mining District, including with us at the Sunshine Mine.
Backed by Electrum, with 30-year track record of success in natural resources
The Company is backed by Electrum, a privately-held global natural resources investment management company. Electrum has a 30-year track record of success in natural resources. Historically, Electrum has focused on a select few, large and world-class precious metals assets located in North America and other “Tier 1” jurisdictions. In addition to its extensive experience in advancing multiple high-quality projects, Electrum has deep and long-held relationships with important stakeholders in the global resources ecosystem. We believe access to Electrum’s specialized skills, knowledge and network substantially enhances our ability to execute our business strategy.
Dr. Thomas S. Kaplan, Chairman of our Board of Directors, is the Chairman and Chief Executive Officer of The Electrum Group LLC (“ TEG ”). Dr. Kaplan has over 30 years of experience in the resources sector, with an established track record in both public and private companies. Dr. Kaplan also serves as Chairman of the board of directors of NOVAGOLD Resources Inc., and previously served as Chairman of the board of directors of Leor Exploration & Production LLC, a natural gas exploration and development company, which he founded in 2003 and sold in 2007 to EnCana Corporation.
Business Strategy
Our business strategy is to develop the Sunshine Complex to its full potential. This includes restarting the Sunshine Mine (including construction of a new mill), unlocking exploration potential both in the Sunshine Mine Core Area and within the large, newly consolidated and highly prospective regional land package, the potential refurbishment, construction and restart of the Sunshine Silver/Copper Refinery and potential development of the Sunshine Antimony Plant.
Our key near- and long-term initiatives include:
•
| Complete infill drilling, a Feasibility Study and detailed engineering for the Sunshine Mine. In 2026 and 2027, we plan to complete infill drilling and engineering designs for the remaining required mine infrastructure and processing facilities. We anticipate this will result in the completion of a Feasibility Study in early 2027 that will combine the technical, economic and risk analyses required to support a final investment decision. We expect these steps will enable us to move to construction with a clear, optimized plan.
|

•
| Complete a Feasibility Study and detailed engineering for the development of the Sunshine Antimony Plant and complete a Feasibility Study for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery. Subject to technical evaluation, we plan to leverage our existing permits to accelerate the design and potential construction of a new antimony refinery – the Sunshine Antimony Plant – and to refurbish the existing Sunshine Silver/Copper Refinery. According to the trajectorE Report, it would cost approximately $90 million to refurbish the Sunshine Silver/Copper Refinery and, assuming production of 30,000 ounces of silver per day and 95% utilization, the Sunshine Silver/Copper Refinery would have the nameplate capacity to produce approximately 10 million ounces of silver per year. We anticipate that these facilities will enable us to refine concentrates on-site, improving margins and reducing reliance on downstream supply chains. Additionally, we expect that the development of the Sunshine Antimony Plant would provide sufficient capacity to process any antimony we produce as well as third-party antimony feed, enabling us to become a critical minerals production hub and potentially the largest producer of finished, refined antimony in the United States.
|

In parallel with these Feasibility Studies and based on the results of these Feasibility Studies, we may evaluate external financing alternatives and strategic transactions with respect to the Sunshine Silver/Copper Refinery and the Sunshine Antimony Plant. The Sunshine Silver/Copper Refinery and the Sunshine Antimony Plant are intended to complement our mining operations by providing downstream processing capabilities. To support this evaluation, we are in the process of selecting an advisory firm to develop a comprehensive roadmap focused on a phased evaluation of refining capabilities for silver, copper, antimony, gallium, and germanium, prioritized by market supply-demand dynamics, projected margin profiles and return on invested capital; a commercial and tolling strategy to define commercial pathways for the processing of both

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Sunshine-mined and third-party feedstock; a value-chain-wide risk mitigation strategy to address metallurgical challenges, feedstock supply consistency and commodity price volatility; an assessment of the optimal corporate structure for the refining business; a financial model of anticipated capital expenditures for the expansion; and the benchmarking of the proposed refining operations against the competitive landscape in North America and globally to ensure a sustainable market position.
•
| Complete construction of the Sunshine Complex and deliver initial production at a competitive capital intensity. We plan to commence mill construction and other key infrastructure upgrades in 2027, and we expect to deliver initial production by the end of 2028. Utilizing our substantial installed infrastructure base, including underground mine infrastructure in which we have invested over the last 15 years, we target achieving a compelling capital intensity for our restart project.
|

•
| Execute on a mine plan that delivers compelling production and cost performance. The Base Case of the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources and is reflective of our above-described development strategy, contemplates producing approximately 6.7 million ounces of payable silver per year on average over the first five years of mine life and approximately 5.8 million ounces of payable silver per year on average over the 24-year mine life at an average AISC of $18.81 per ounce of silver produced (excluding potential copper and lead by-product credits).
|

•
| Conduct exploration activities near the Sunshine Mine and across the broader land package. We intend to ramp up our exploration activities to identify new mineralized zones in and around the Sunshine Mine, including the Upper Country, down-dip and horizontal extensions of current veins which are open at depth and underexplored “gaps” in the primary six-mile strike length corridor of the Sunshine Mine Core Area, as well as other targets within our highly prospective and newly consolidated district-scale land package around the Sunshine Mine. These activities will seek to uncover new, high-grade silver and antimony deposits that can support expanded production scale and/or extend mine life. Consistent with Scout’s recommended roadmap, our exploration planning contemplates systematic sampling, mapping and geochemistry along with an approximately 15,000-meter surface drill program in 2026 for testing target areas on our land package, including the Pine Creek and Rock Creek areas. For the 2026 field season, we plan to spend approximately $10 million for the planned exploration of the broader land package.
|

•
| Maintain focus on industry-leading safety standards and strong track record of environmental management and community engagement. We strive to execute our exploration, development and mine plan while holding safety as a top priority through rigorous protocols. Our goal is to combine operational excellence with a culture of safety to deliver reliable performance on development, production, cost and safety over the long term. We are also focused on environmental initiatives and community relations in every aspect of our operations. Through our longstanding commitment to environmental compliance, partnerships with government agencies, and investments into zero-liquid-discharge water technologies, tailings rehabilitation, and modernized environmental systems, we remain committed to the protection of our neighboring communities. Additionally, we plan to continue to cultivate positive relationships with local stakeholders including residents, indigenous groups such as the Coeur d’Alene Tribe, and mining service vendors.
|

•
| Identify and pursue other growth opportunities. We will continue to evaluate value-enhancing growth initiatives, with a focus on projects or partnerships that align with our core competencies. Given our management team’s and Board’s strong track record in exploration, development and mergers and acquisitions, such initiatives may include the pursuit of acquisitions of similarly attractive silver and critical minerals-focused projects or other business combinations.
|

Risk Factors
Before you invest in our common stock, you should carefully consider all the information in this prospectus, including matters set forth under “ Risk Factors .” These risks represent challenges to the successful implementation of our strategy and future profitability of our business. These risks include:
•
| We may not generate any operating revenues or achieve profitable operations.
|

•
| We are dependent on the Sunshine Mine for our future operations. The Sunshine Mine does not currently have any Proven Mineral Reserves or Probable Mineral Reserves, or any antimony, copper, lead, gallium or germanium reserves or resources, as defined under S-K 1300.
|

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•
| Mineral Resource calculations at the Sunshine Mine are only estimates and may have to be recalculated as a result of changes in metal prices, further exploration or development activity, inaccurate or incomplete historical mining records or actual production experience.
|

•
| Our mineral exploration efforts are highly speculative in nature and may be unsuccessful.
|

•
| We may not move forward with the refurbishment, construction or restart of the Sunshine Silver/Copper Refinery nor the development of the Sunshine Antimony Plant, and the operation of the Sunshine Silver/Copper Refinery and the potential Sunshine Antimony Plant would be subject to certain risks associated with mining refining operations.
|

•
| We have historically experienced negative operating cash flow from operating activities.
|

•
| We will require additional financing in the future to bring the Sunshine Mine into sustained commercial operation.
|

•
| The title to some of our mineral properties may be uncertain or defective, thus risking our investment in such properties.
|

•
| The prices of silver, copper, lead and antimony are subject to change and a substantial or extended decline in the prices of silver, copper, lead and antimony could materially and adversely affect our revenues and the value of our mineral property.
|

•
| The U.S. government, as well as state and local governments, extensively regulate mining operations, which impose significant actual and potential costs on us, and future regulation could increase those costs or limit our ability to produce silver and other metals.
|

•
| We are required to obtain, maintain and renew environmental, construction and mining permits, which is often a costly and time-consuming process and may ultimately not be possible.
|

•
| Electrum and its affiliates will continue to have substantial control over us after the completion of this offering, which could delay or prevent a change of corporate control or result in the entrenchment of management and/or our Board of Directors.
|

Implications of Becoming an Emerging Growth Company
As a company with less than $1.235 billion in revenue during our last fiscal year, we qualify as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 (the “ JOBS Act ”). An emerging growth company may take advantage of specified reduced reporting and other requirements that are otherwise applicable generally to public companies. These provisions include:
•
| we are not required to engage an auditor to report on our internal controls over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act of 2002 (the “ Sarbanes-Oxley Act ”);
|

•
| we are only required to include two years of audited consolidated financial statements in this prospectus, in addition to any required interim financial statements;
|

•
| we are not required to comply with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor’s report providing additional information about the audit and the financial statements (i.e., an auditor discussion and analysis);
|

•
| we are only required to provide reduced disclosure in “ Management’s Discussion and Analysis of Financial Condition and Results of Operations ;”
|

•
| we are not required to submit certain executive compensation matters to stockholder advisory votes, such as “say-on-pay,” “say-on-frequency” and “say-on-golden parachutes;” and
|

•
| we are not required to disclose certain executive compensation related items such as the correlation between executive compensation and performance and comparisons of the chief executive officer’s compensation to median employee compensation.
|

We may take advantage of these provisions until the last day of our fiscal year following the fifth anniversary of the completion of this offering or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company upon the earliest of: (i) the last day of the first fiscal year in which our annual gross revenues are $1.235 billion or more; (ii) the date on which we have, during the previous rolling three-year period, issued

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more than $1.0 billion in non-convertible debt securities; or (iii) the last day of the fiscal year in which the market value of our common stock held by non-affiliates exceeded $700 million as of June 30 of such fiscal year. Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company,” which would allow us to take advantage of many of the same exemptions from disclosure requirements, including reduced disclosure obligations regarding executive compensation in this prospectus and our periodic reports and proxy statements.
We may take advantage of some of the reduced disclosure obligations listed above in this prospectus and may elect to take advantage of other reduced reporting requirements in future filings.
Under the JOBS Act, emerging growth companies also can delay adopting new or revised accounting standards until such time as those standards would otherwise apply to private companies. We have elected to avail ourselves of this extended transition period and, as a result, we will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for public companies that are not emerging growth companies.
For risks related to our status as an emerging growth company, see “ Risk Factors—Risks Related to This Offering and Our Common Stock—The requirements of being a public company may strain our resources, divert management’s attention and affect our ability to attract and retain executive management and qualified board members, which could make it difficult to manage our business, particularly after we are no longer an “emerging growth company .”
Corporate Information
In May 2010, our wholly-owned subsidiary Silver Opportunity Partners LLC (“ SOP ”) acquired from Sterling Mining Company (“ Sterling ”), through Sterling’s bankruptcy proceedings, the majority of the operating facilities and equipment at the Sunshine Mine, including a lease on the Sunshine Mine that included an option to purchase title to the Sunshine Mine from Sunshine Precious Metals, Inc. (“ SPMI ”). In July 2010, SOP closed the purchase option in the lease to obtain title to the Sunshine Mine and acquired the remaining operating facilities and equipment. In October 2013, our wholly-owned subsidiary Sunshine Refining Company (“ SRC ”) acquired the Sunshine Silver/Copper Refinery from Formation Metals Inc. In October 2020, as part of a corporate reorganization of Gatos Silver, Inc. (“ Gatos Silver ”), which had previously been named Sunshine Silver Mining & Refining Corporation, we were formed to become the owner of SOP and SRC. We were spun out from Gatos Silver prior to Gatos Silver’s initial public offering in October 2020, and we changed our name to Sunshine Silver Mining & Refining Company.
Our principal executive office is located at 2209 Big Creek Rd, Kellogg, Idaho 83837. Our telephone number is (208) 783-1700.

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THE OFFERING
This summary highlights information presented in greater detail elsewhere in this prospectus. This summary is not complete and does not contain all the information you should consider before investing in our common stock. You should carefully read this entire prospectus before investing in our common stock including “Risk Factors” and our consolidated financial statements and related notes included elsewhere in this prospectus.
Issuer
Sunshine Silver Mining & Refining Company.
Common stock offered in firm commitment offering
20,000,000 shares.
Common stock to be outstanding after the completion of this offering
140,840,360 shares (or 143,840,360 shares if the underwriters exercise their option to purchase additional shares of our common stock from us in full).
Option to purchase additional shares of common stock
3,000,000 shares.
Use of proceeds
We estimate that the net proceeds to us from this offering will be approximately $276.6 million, or approximately $318.9 million if the underwriters exercise their option to purchase additional shares of our common stock from us in full, assuming an initial public offering price of $15.00 per share, which is the midpoint of the range set forth on the cover page of this prospectus, and after deducting underwriting discounts and commissions and estimated offering expenses payable by us.
We intend to use the net proceeds from this offering to conduct a Feasibility Study for the restart of the Sunshine Mine including the construction of a new mill, a Feasibility Study for the development of the Sunshine Antimony Plant and a Feasibility Study for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery, for infill drilling and associated underground development costs, mining equipment and mine infrastructure purchases, as well as for mine development and overhead expenses, project management expenses, exploration activities in underdefined areas on our land package, and general corporate purposes.
See “ Use of Proceeds .”
Voting rights
Holders of our common stock are entitled to one vote per share. See “ Description of Capital Stock .”
Directed share program
At our request, the underwriters have reserved for sale, at the initial public offering price, up to 5% of the common stock offered by this prospectus for sale to our directors, officers, employees, consultants and existing stockholders and other persons having a relationship with us, such as suppliers, or having a relationship with our directors, officers, employees, consultants and existing stockholders. If these persons purchase reserved shares, it will reduce the number of shares available for sale to the

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general public. Any reserved shares that are not so purchased will be offered by the underwriters to the general public on the same terms as the other shares offered by this prospectus.
Controlled company status
Electrum will control approximately 60.7% of the voting power of our common stock outstanding upon completion of this offering (or approximately 59.5% if the underwriters exercise their option to purchase additional shares of our common stock from us in full). As a result, we will be a “controlled company” within the meaning of the corporate governance rules of the NYSE, and we have elected not to comply with certain corporate governance requirements of the NYSE. See “ Management—Controlled Company Status .” As a result, you will not have the same protections afforded to stockholders of companies that are subject to all of the corporate governance requirements of the NYSE.
As long as Electrum beneficially owns a majority of the voting power of our outstanding shares of common stock, Electrum will generally be able to control the outcome of matters submitted to our stockholders for approval, including the election of directors, without the approval of our other stockholders.
Dividend policy
We have never declared or paid any cash dividends on our capital stock. We do not intend to pay any dividends in the foreseeable future and currently intend to retain all future earnings to finance our business. See “ Dividend Policy .”
Risk factors
See “ Risk Factors ” for a discussion of factors you should carefully consider before deciding whether to invest in our common stock.
Common stock listing
We have been approved to list our common stock on NYSE under the symbol “SSMR.”
The number of shares of our common stock that will be outstanding after the completion of this offering is based on 116,509,480 shares of common stock outstanding as of March 31, 2026, the issuance of 4,330,880 shares of our common stock upon the net exercise of warrants to purchase 5,354,700 shares of our common stock outstanding as of March 31, 2026 at an exercise price of $2.87 per share, which will occur immediately prior to the completion of this offering (the “ Warrant Net Exercise ”), and the issuance and sale of 20,000,000 shares of common stock in this offering. Unless otherwise indicated, all information in this prospectus, including the number of shares that will be outstanding after the completion of this offering and other share-related information, excludes:
•
| 8,573,000 shares of common stock issuable upon the exercise of stock options outstanding as of March 31, 2026, at a weighted average exercise price of $3.94 per share;
|

•
| 66,664 shares of common stock issuable upon the settlement of the Non-Employee Director Initial RSUs (as defined in “Executive and Director Compensation—Director Compensation”), assuming an initial public offering price of $15.00 per share, which is the midpoint of the range set forth on the cover page of this prospectus;
|

•
| 8,644,898 additional shares of common stock unallocated and reserved for future issuance under the Amended and Restated LTIP (as defined below), as well as any automatic increases in the number of shares of common stock reserved for future issuance under the Amended and Restated LTIP; and
|

•
| 9,375,000 shares of common stock issuable upon the exercise of warrants outstanding as of March 31, 2026, at a weighted average exercise price of $5.00 per share (the “ Private Placement Warrants ”).
|

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See “ Executive and Director Compensation ” and “ Description of Capital Stock .”
Unless otherwise indicated, all information in this prospectus assumes or gives effect to:
•
| the filing and effectiveness of our Third Amended and Restated Certificate of Incorporation, which will occur immediately prior to the completion of this offering;
|

•
| an initial public offering price of $15.00 per share of common stock, which is the midpoint of the range set forth on the cover page of this prospectus;
|

•
| the Warrant Net Exercise;
|

•
| a ten-for-one stock split of our common stock, which was effectuated on May 11, 2026 (the “ Stock Split ”);
|

•
| no exercise of outstanding options described above;
|

•
| no exercise by the underwriters of their option to purchase additional shares of our common stock from us; and
|

•
| no purchase of common stock in this offering by directors, officers or existing stockholders.
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SUMMARY CONSOLIDATED FINANCIAL DATA
We prepared the summary consolidated financial data using our consolidated financial statements for each of the periods presented. The unaudited summary consolidated financial data for the three months ended March 31, 2026 and 2025 and the unaudited summary consolidated financial data as of March 31, 2026 were derived from our unaudited consolidated financial statements and related notes included elsewhere in this prospectus. The summary consolidated financial data for each fiscal year in the two-year period ended December 31, 2025 was derived from our audited consolidated financial statements and related notes included elsewhere in this prospectus. In our opinion, the unaudited summary consolidated financial data set forth below has been prepared on a basis consistent with our audited consolidated financial statements and contain all adjustments, consisting only of normal and recurring adjustments, necessary for the fair statement of such data. You should read this financial data in conjunction with “ Management’s Discussion and Analysis of Financial Condition and Results of Operations ” and our consolidated financial statements and related notes included elsewhere in this prospectus.

March 31,
|
|
| Year Ended December 31,
|

|
|
| 2026
|
|
| 2025
|
|
| 2025
|
|
| 2024
|

|
|
| (in thousands, except for share and per share amounts)
|
Statement of Operations Data:

|
|
|
|
|
|
|
|
|
|
|
|
|
Sales
|
|
| $ —
|
|
| $ 41
|
|
| $ 501
|
|
| $ 96
|
Operating Expenses:

|
|
|
|
|
|
|
|
|
|
|
|
|
Exploration
|
|
| —
|
|
| —
|
|
| 262
|
|
| —
|
Pre-development
|
|
| 7,400
|
|
| 1,111
|
|
| 16,990
|
|
| 2,662
|
General and administrative
|
|
| 5,599
|
|
| 1,614
|
|
| 14,084
|
|
| 5,749
|
Depreciation and amortization
|
|
| 365
|
|
| 133
|
|
| 849
|
|
| 577
|
Accretion expense
|
|
| 29
|
|
| 28
|
|
| 111
|
|
| 104
|
Cost of goods sold (exclusive of items shown separately above)
|
|
| —
|
|
| 20
|
|
| 344
|
|
| 47
|
Operating loss
|
|
| (13,394)
|
|
| (2,865)
|
|
| (32,138)
|
|
| (9,043)
|
Other income (expense):

|
|
|
|
|
|
|
|
|
|
|
|
|
Interest expense
|
|
| (10)
|
|
| (1,177)
|
|
| (2,904)
|
|
| (3,872)
|
Interest income
|
|
| 153
|
|
| 2
|
|
| 299
|
|
| 23
|
Total other income (expense)
|
|
| 143
|
|
| (1,175)
|
|
| (2,605)
|
|
| (3,849)
|
Income and mining tax expense
|
|
| —
|
|
| —
|
|
| —
|
|
| —
|
Net and comprehensive loss
|
|
| (13,251 )
|
|
| (4,040 )
|
|
| (34,743 )
|
|
| (12,892 )
|
Basic and diluted loss per share of common stock
|
|
| $ (0.11)
|
|
| $ (0.05)
|
|
| $ (0.36)
|
|
| $ (0.15)
|
Weighted average number of basic and diluted shares of common stock outstanding
|
|
| 116,509,480
|
|
| 85,439,630
|
|
| 97,291,648
|
|
| 85,439,630
|

|
|
|
|
|
|
|
|
|
|
|
|
|

March 31,
|
|
| Year Ended December 31,
|

|
|
| 2026
|
|
| 2025
|
|
| 2025
|
|
| 2024
|

|
|
| (in thousands)
|
Cash Flow Data:

|
|
|
|
|
|
|
|
|
|
|
|
|
Net cash used in operating activities
|
|
| $ (10,616)
|
|
| $ (2,237)
|
|
| $(24,423)
|
|
| $(7,724)
|
Net cash used in investing activities
|
|
| (1,535)
|
|
| (352)
|
|
| (10,452)
|
|
| (863)
|
Net cash provided by financing activities
|
|
| (224)
|
|
| 2,866
|
|
| 63,883
|
|
| 8,801
|

|
|
|
|
|
|
|
|
|
|
|
|
|

TABLE OF CONTENTS

|
|
|
|
|
|
|
Cash and cash equivalents
|
|
| $18,601
|
|
| $ 295,211
|
Total assets
|
|
| 59,997
|
|
| 336,607
|
Total liabilities
|
|
| 9,861
|
|
| 9,861
|
Total stockholders’ equity
|
|
| 50,136
|
|
| 326,746
|

|
|
|
|
|
|
|

(1)

| The as adjusted information gives effect to the Warrant Net Exercise and the issuance and sale of 20,000,000 shares of common stock in this offering, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. The as adjusted information is illustrative only and will change based on the actual initial public offering price and other terms of this offering determined at pricing. A $1.00 increase (decrease) in the assumed initial public offering price of $15.00 per share, which is the midpoint of the range set forth on the cover page of this prospectus, would increase (decrease) as adjusted cash and cash equivalents, total assets and total stockholders’ equity by $18.8 million, assuming the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same. A 1,000,000 share increase (decrease) in the number of shares of common stock offered by us would increase (decrease) as adjusted cash and cash equivalents, total assets and total stockholders’ equity by $14.1 million, assuming the assumed initial public offering price remains the same.
|

TABLE OF CONTENTS
RISK FACTORS
You should carefully consider the following risk factors that may affect our business, future operating results and financial condition, as well as the other information set forth in this prospectus, before making a decision to invest in our common stock. If any of the following risks actually occurs, our business, financial condition or results of operations would likely be materially and adversely affected. In such case, the trading price of our common stock would likely decline, and you may lose all or part of your investment. The risks below are not the only ones we face. Additional risks not currently known to us or that we currently deem immaterial may also adversely affect us.
Risks Related to Our Business and Industry
We may not generate any operating revenues or achieve profitable operations.
We acquired the Sunshine Mine in 2010 but have not yet generated any operating revenue. We expect the Sunshine Mine to deliver initial production by the end of 2028, but we may not be successful in resuming production at the Sunshine Mine. The Sunshine Mine has not been a producing mine since 2008; however, it remains active and continues to be regulated as an operating mine and is therefore subject to strict regulation by federal, state and local authorities. See “ —Risks Related to Government Regulations .” We anticipate that we will continue to incur operating costs without realizing any revenues at the Sunshine Mine until at least production is restarted. Further, we expect to continue to incur losses until such time as the Sunshine Mine generates sufficient revenues to fund our continuing operations. If we are unable to generate significant revenues at the Sunshine Mine, we will not be able to earn profits or continue operations.
We are dependent on the Sunshine Mine for our future operations. The Sunshine Mine does not currently have any Proven Mineral Reserves or Probable Mineral Reserves, or any antimony, copper, lead, gallium or germanium reserves or resources, as defined under S-K 1300.
The Sunshine Mine does not have identified Proven Mineral Reserves or Probable Mineral Reserves. The costs, timing and complexities of upgrading the Mineral Resources at the Sunshine Mine to Proven Mineral Reserves and Probable Mineral Reserves may be greater than we anticipate. Mineral exploration and development involves a high degree of risk that even a combination of careful evaluation, experience and knowledge cannot eliminate, and few properties that are explored are ultimately developed into producing mines. Our mineral exploration program at the Sunshine Mine may not establish the presence of any Proven Mineral Reserves or Probable Mineral Reserves. The failure to establish any Proven Mineral Reserves or Probable Mineral Reserves would severely restrict our ability to implement our strategies for long-term growth.
Although we plan to produce antimony, copper and lead by-products, as well as other critical minerals, which may include gallium and germanium, once operations restart at the Sunshine Mine, SLR and SRK have not estimated antimony, copper, lead, gallium or germanium Mineral Reserves or Mineral Resources, and we may not be able to demonstrate reasonable prospects for economic extraction of these by-products or other critical minerals.
Mineral Resource calculations at the Sunshine Mine are only estimates and may have to be recalculated as a result of changes in metal prices, further exploration or development activity, inaccurate or incomplete historical mining records or actual production experience.
Calculations of Mineral Resources at the Sunshine Mine are only estimates and depend on geological interpretation and statistical inferences or assumptions drawn from drilling and sampling analysis, which might prove to be materially inaccurate. There is a degree of uncertainty attributable to the calculation of Mineral Resources. Until Mineral Resources are actually mined and processed, the quantity of metal and grades must be considered as estimates only and no assurance can be given that the indicated levels of metals will be produced. In making determinations about whether to advance our project to development, we must rely upon estimated calculations for the Mineral Resources and grades of mineralization at the Sunshine Mine. There can be no guarantee that technical and economic parameters underlying the Mineral Resource calculations or Mineral Resource estimates included in the Initial Assessment will in fact be achieved in the future, and unexpected metallurgical challenges may cause actual results to differ from expected results.
The estimation of Mineral Resources is a subjective process that is partially dependent upon the judgment of the persons preparing the estimates. The process relies on the quantity and quality of available data and is based on knowledge, mining experience, statistical analysis of drilling results and industry practices. Valid estimates made at a given time may significantly change when new information becomes available.

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We have relied, and the disclosure in the Sunshine Technical Report Summary is based, in part, on historical drilling and on data and documentation compiled by previous owners of the Sunshine Mine that cannot be completely verified due to lack of access to certain historically mined areas and the lack of quality assurance and quality control information on the historic assays. We expect that, in the process of further drilling and development work, we will further delineate the grade, shape and characteristics of the resource, which may require adjustments to the Mineral Resource estimate. To the extent that future work shows that any historical mining records were inaccurate, incomplete, or not correctly reflected in our estimated Mineral Resources, our estimated Mineral Resources may have to be recalculated. For example, in February 2026, we identified, through ongoing review of historical records, that a portion of the Mineral Resources reflected in our Mineral Resource estimate had already been mined, which resulted in a reduction of the estimated Mineral Resource.
Estimated Mineral Resources may also have to be recalculated based on changes in metal prices, further exploration or development activity or actual production experience. Any such changes or inaccuracies could materially and adversely affect estimates of the volume or grade of mineralization, estimated metallurgical recovery or other important factors that influence Mineral Resource estimates. The extent to which Mineral Resources may ultimately be reclassified as Mineral Reserves is dependent upon the demonstration of their profitable recovery. Any material changes in volume and grades of mineralization will affect the economic viability of placing a property into production and a property’s return on capital. We cannot provide assurance that mineralization can be mined or processed profitably.
Mineral Resource estimates have been determined and valued based on assumed metal prices, cut-off grades and operating costs that may prove to be inaccurate. Extended declines in the market price for silver may render portions of our mineralization uneconomic and result in reduced reported volume and grades, which in turn could have a material adverse effect on our financial performance, financial position and results of operations.
In addition, Mineral Resource estimates involve significant reliance on Inferred Mineral Resources, which may increase the risk of overestimation. Inferred Mineral Resources are subject to significant uncertainty as to their existence and as to their economic and legal feasibility. The level of geological uncertainty associated with an Inferred Mineral Resource is too high to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability.
Our mineral exploration efforts are highly speculative in nature and may be unsuccessful.
Mineral exploration is highly speculative in nature, involves many uncertainties and risks and is frequently unsuccessful. It is performed to demonstrate the dimensions, position and mineral characteristics of mineral deposits, estimate Mineral Resources, assess amenability of the deposit to mining and processing scenarios and estimate potential deposit value. Once mineralization is discovered, it may take a number of years from the initial exploration phases before production is possible, during which time the feasibility of the project may change adversely. Substantial expenditures are required to establish Proven Mineral Reserves and Probable Mineral Reserves, to determine processes to extract the metals and, if required, to construct mining and processing facilities and obtain the rights to the land and resources required to develop the mining activities.
In addition, the grade of mineralization ultimately mined may differ from that indicated by drilling results and such differences could be material. Short-term factors, such as the need for orderly development of mineral deposits or the processing of new or different grades, may have an adverse effect on mining operations. There can be no assurance that minerals recovered in small scale laboratory tests will be duplicated in large scale tests under on-site conditions or in production scale operations. Material changes in geological resources, grades or metallurgical recovery may affect the economic viability of our project.
Exploration stage properties have no Mineral Reserves disclosed and only have estimates of Mineral Resources and/or Exploration Targets. Mineral Resource estimates are, to a large extent, based upon the interpretation of geological data and modeling obtained from drill holes and other sampling techniques, initial assessments that derive estimates of operating costs based upon anticipated tonnage and grades of material to be mined and processed, the configuration of the deposit, expected metallurgical recovery of metal from the mill feed material, facility and equipment capital and operating costs, anticipated climatic conditions and other factors. As a result, actual operating costs and economic returns based upon development of Mineral Resources may differ significantly from those originally estimated. Significant decreases in actual or expected commodity prices may also mean mineralization, once found, will be uneconomical to mine.

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In addition, our ongoing exploration work may not result in any additional resource definition, an extension of our mine life or an expansion of annual production. While we intend to explore the Upper Country and other areas surrounding the Sunshine Mine, the mountainous and forested topography of such areas may impact our ability to deploy drill rigs.
Our anticipated processing ability may be adversely impacted by certain circumstances.
A number of factors could affect our ability to process the quantities of metals that we recover or receive from third-parties and our ability to efficiently handle certain quantities of processed materials, including, but not limited to, the presence of oversized material at the crushing stage; material showing breakage characteristics different than those planned; material with grades outside of planned grade range; the presence of deleterious materials in ratios different than expected; material drier or wetter than expected, due to natural or environmental effects; and materials having viscosity or density different than expected.
The occurrence of one or more of the circumstances described above could affect our ability to process the number of tons planned, recover valuable materials, remove deleterious materials and produce planned quantities of concentrates. In turn, this may result in lower throughput, lower recoveries, increased downtime, increased costs or some combination of all of the foregoing. While minor issues of this nature are part of normal operations, unexpected conditions may materially and adversely affect our business, results of operations or financial condition.
We may not move forward with the refurbishment, construction or restart of the Sunshine Silver/Copper Refinery nor the development of the Sunshine Antimony Plant, and the operation of the Sunshine Silver/Copper Refinery and the potential Sunshine Antimony Plant would be subject to certain risks associated with mining refining operations.
We are conducting a Feasibility Study for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery and a Feasibility Study for the development of the Sunshine Antimony Plant in the Sunshine Complex as part of our technical evaluation ahead of a potential decision to pursue the development of the Sunshine Antimony Plant. Our plans with respect to the Sunshine Silver/Copper Refinery and the potential Sunshine Antimony Plant are dependent on the outcome of such Feasibility Studies, as well as technical and engineering evaluations and other external factors outside of our control. We may not move forward with either the refurbishment, construction or restart of the Sunshine Silver/Copper Refinery or the development of the Sunshine Antimony Plant, or any other antimony processing or refinery plans, and we may in the future decide to delay, revise or abandon such plans.
If we move forward with either the refurbishment, construction or restart of the Sunshine Silver/Copper Refinery or the development of the potential Sunshine Antimony Plant, such plans will be subject to certain risks associated with mining refining operations, including but not limited to, considerable resources and costs expenditures, risks inherent to production, construction costs and delays, macroeconomic factors and the ability to obtain required approvals and permits. If we proceed to refurbish, construct and restart the Sunshine Silver/Copper Refinery or develop the Sunshine Antimony Plant, we may not be able to achieve projected capacity on the timeline expected or at all. Historical quantities and production volume of silver, copper and antimony around the Sunshine Mine are not indicative of future production, and it may be difficult, expensive or impossible to source concentrate from third parties on attractive terms or at all. We also may not be able to achieve anticipated positive synergies from having refining capacity on-site, such as improving margins and reducing reliance on downstream supply chains, which may adversely affect our operations and profitability. Depending on the results of the Feasibility Studies for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery and the development of the Sunshine Antimony Plant, and depending on the performance of the Sunshine Silver/Copper Refinery and the Sunshine Antimony Plant (if constructed), we may consider public or private financing alternatives and strategic transactions including partnerships or a spin-off or sale.
Furthermore, if we move forward with either the refurbishment, construction or restart of the Sunshine Silver/Copper Refinery or the development of the potential Sunshine Antimony Plant, the operation of either involves many risks, which may include a breakdown or failure of the equipment and systems, variations in the feed concentrate (including feed from third parties), higher than anticipated operating costs, lack of qualified labor, inability to operate within environmental permit parameters, inability to produce refined products to required specifications, inability to produce saleable metal, inability to effectively manage distribution channels, changes in markets and market prices for the refined products and operating cost increases, as well as the risk of performance below expected levels of output or efficiency due to the inability to secure long-term tolling arrangements or otherwise. Such events could negatively impact our business, results of operations or financial condition.

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Actual capital costs, operating costs, production and economic returns may differ significantly from those we have anticipated and there are no assurances that any future development activities will result in profitable mining operations.
The capital costs to take the Sunshine Mine into production may be significantly higher than those set forth in the Sunshine Technical Report Summary. We will ultimately base our decisions about the restart of the Sunshine Mine, including the construction of a new mill, on a Feasibility Study. We have not yet prepared a Feasibility Study for the Sunshine Mine. Our evaluations of our business and prospects are subject to change, including after any Feasibility Study has been conducted, which could materially and adversely affect our prospects.
Additionally, the actual operating costs at the Sunshine Mine will depend upon changes in the availability and prices of labor, equipment and infrastructure, variances in metal recovery and mining rates from those assumed in the mining plan, operational risks, changes in governmental regulation, including taxation, environmental, permitting and other regulations and other factors, many of which are beyond our control. Due to any of these or other factors, the operating costs at the Sunshine Mine may be significantly higher than those set forth in the Sunshine Technical Report Summary. As a result of higher capital and operating costs, production and economic returns may differ significantly from those set forth in the Sunshine Technical Report Summary and there are no assurances that any future development activities will result in profitable mining operations.
We have historically experienced negative operating cash flow from operating activities.
We had negative operating cash flow for each of the three months ended March 31, 2026 and 2025 and each of the years ended December 31, 2025 and 2024, and we anticipate that the holding costs at the Sunshine Mine and Sunshine Silver/Copper Refinery and the general and administrative costs of our corporate office will cause negative operating cash flow in future periods. For the three months ended March 31, 2026 and 2025, we incurred a net loss of approximately $13.3 million and $4.0 million, respectively, and our net cash used in operating activities was approximately $10.6 million and $2.2 million, respectively. For the years ended December 31, 2025 and 2024, we incurred a net loss of approximately $34.7 million and $12.9 million, respectively, and our net cash used in operating activities was approximately $24.4 million and $7.7 million, respectively. Although we anticipate that we will have access to sufficient financial resources to fund our operation, we cannot guarantee that we will have positive cash flow in the future or have access to sufficient financial resources to fund our operations. To the extent that we have negative cash flow in any future period, a portion of the proceeds from this offering may be used to fund our operating activities. See “ Use of Proceeds .”
Historical production at the Sunshine Mine may not be indicative of the potential for future development.
There is currently no commercial production at the Sunshine Mine and, since acquiring ownership, we have not recorded any revenues from operations at the Sunshine Mine. You should not rely on the fact that there were historical mining operations at the Sunshine Mine as an indication that we will ever have future successful commercial operations at the Sunshine Mine. In order for us to develop new mining operations at the Sunshine Mine, we will be required to incur substantial operating expenses and capital expenditures to refurbish and/or replace existing infrastructure.
Land reclamation and mine closure may be burdensome and costly.
Land reclamation and mine closure requirements are generally imposed on mineral exploration companies, such as ours, which require us, among other things, to minimize the effects of land disturbance. Such requirements may include controlling the discharge of potentially dangerous effluents from a site and restoring a site’s landscape to its pre-exploration form. Our undiscounted reclamation obligations were estimated at approximately $4.2 million as of March 31, 2026, and the corresponding asset retirement obligation, which reflects the estimated present value of future closure obligations, was approximately $1.8 million. However, the actual costs of reclamation and mine closure are uncertain and may exceed planned expenditures due to factors including, among others, changes in the nature of waste rock, tailings or soil conditions, revegetation requirements, fuel or contractor cost increases and/or revisions to government regulations. Therefore, the amount that we are required to spend could be materially higher than current estimates. Any additional amounts required to be spent on reclamation and mine closure may have a material adverse effect on our financial performance, financial position and results of operations and may cause us to alter our operations. In addition, we are required to maintain financial assurances, such as letters of credit, to secure reclamation obligations under certain laws and regulations. The failure to acquire, maintain or renew such financial assurances could subject us to fines and penalties or suspension of our operations. Letters of credit or other forms of financial assurance represent only a portion of the total amount of money that will be spent

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on reclamation over the life of a mine’s operation. Although we include liabilities for estimated reclamation and mine closure costs in our financial statements, it may be necessary to spend more than what is projected to fund required reclamation and mine closure activities. Additionally, even if we cease exploration at the Sunshine Mine, we will be required to expend cash and other resources to satisfy ongoing care and maintenance obligations at the Sunshine Mine, which obligations include controlling ground water, monitoring and sampling permitted facilities and ultimately reclaiming our tailings storage area.
We will require additional financing in the future to bring the Sunshine Mine into sustained commercial operation.
We intend to use the net proceeds from this offering to conduct a Feasibility Study for the restart of the Sunshine Mine including the construction of a new mill, a Feasibility Study for the development of the Sunshine Antimony Plant and a Feasibility Study for the refurbishment, construction and restart of the Sunshine Silver/Copper Refinery, for infill drilling and associated underground development costs, mining equipment and mine infrastructure purchases, as well as for mine development and overhead expenses, project management expenses, exploration activities in underdefined areas on our land package, and general corporate purposes. See “ Use of Proceeds .” We anticipate that our total expenditures related to the Feasibility Studies will be approximately $41 million and we expect to spend approximately $15 million on infill drilling and associated underground development over the next 10 months. In addition, we expect to spend approximately $25 million on greenfield and brownfield exploration projects over the next 18 months. We will require additional funding in the future to bring the Sunshine Mine into sustained commercial production. Our ability to raise such additional financing will depend on a number of factors, including the price of silver, the amount of capital required for the advanced studies, the economics of the Sunshine Mine, interest rates and operating costs.
We expect to raise additional funds through sales of equity or debt, project financing, joint venture funding or some combination thereof. Access to additional capital may not, however, be available on terms acceptable to us, at acceptable prices, or at all. Failure to obtain sufficient financing may result in the delay or indefinite postponement of exploration, drilling, development or production at the Sunshine Mine. Furthermore, even if we raise sufficient additional capital, there can be no assurance that we will achieve profitability or positive cash flow. In addition, any future equity offering will further dilute your equity interest in us and any future debt financing will require us to dedicate a portion of our cash flow to payments on indebtedness and will limit our flexibility in planning for or reacting to changes in our business.
We rely on third-party contractors and other parties.
As we continue with the exploration and advancement of the Sunshine Mine and any other projects we may acquire in the future, timely and cost-effective completion of work will depend largely on the performance of contractors, consultants, geologists, engineers and other parties. For example, our Mineral Resource estimates and potential environmental liability estimates were prepared by third-party consultants. Substantial expenditures are required to construct mines, to establish Mineral Resources and Reserves estimates through drilling, to carry out environmental and social impact assessments, to establish closure requirement estimates, to develop metallurgical processes and to develop the exploration and plant infrastructure at any particular site. If any of our contractors or consultants do not perform to accepted or expected standards, we may be required to hire different contractors or consultants to complete tasks, which may impact schedules and add costs to the Sunshine Mine and any other projects we may acquire in the future, and in some cases, lead to significant risks and losses.
The restart of the Sunshine Mine will be subject to certain risks associated with establishing new mining operations.
The Base Case in the Sunshine Technical Report Summary, which assumes the mining of both Indicated Mineral Resources and Inferred Mineral Resources, indicates that the Sunshine Mine is a silver project with an after-tax NPV of approximately $1.4 billion, assuming a 5% discount rate, the prevailing industry standard discount rate for evaluating precious metals projects in North America, an after-tax internal rate of return of approximately 38.3% and a 24-year mine life at modeled metals’ prices, whereas the Indicated Only Case in the Sunshine Technical Report Summary indicates that the Sunshine Mine is a silver project with an after-tax NPV of approximately $270 million, assuming a 5% discount rate, the prevailing industry standard discount rate for evaluating precious metals projects in North America, an after-tax internal rate of return of approximately 21.1% and a 10-year mine life at modeled metals’ prices. If the restart of the Sunshine Mine, including the construction of a new mill, is found to be economically feasible, its development will require maintaining and obtaining additional permits and financing, and the construction and operation of mines, processing facilities and related infrastructure.

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As a result, we will be subject to certain risks associated with establishing new mining operations, including:
•
| the timing and cost, which can be considerable, of the construction of mining and processing facilities and related infrastructure;
|

•
| the availability and cost of skilled labor, mining equipment and principal supplies needed for operations, including explosives, fuels, chemical reagents, water, power, equipment parts and lubricants;
|

•
| the availability and cost of appropriate smelting and refining arrangements;
|

•
| the need to maintain and obtain additional necessary environmental and other governmental approvals and permits, the timing of the receipt of those approvals and permits and the restrictions set forth in those approvals and permits;
|

•
| the availability of funds to finance construction and development activities;
|

•
| industrial accidents;
|

•
| mine failures, shaft failures or equipment failures;
|

•
| tailings storage facility failures;
|

•
| natural phenomena such as inclement weather conditions, floods, droughts, rock slides and seismic activity;
|

•
| unusual or unexpected geological and metallurgical conditions;
|

•
| exchange rate and commodity price fluctuations;
|

•
| high rates of inflation;
|

•
| interest rate fluctuations;
|

•
| health pandemics;
|

•
| potential opposition from non-governmental organizations, environmental groups or local groups, which may delay or prevent development activities; and
|

•
| restrictions or regulations imposed by governmental or regulatory authorities, including with respect to environmental matters or environmental permits.
|

The costs, timing and complexities of developing the Sunshine Mine may be greater than anticipated. Cost estimates may increase significantly as more detailed engineering work is completed. It is common in mining operations to experience unexpected costs, problems and delays during construction, development and mine start-up. In addition, the cost of producing silver-bearing concentrates that are of acceptable quality to smelters may be significantly higher than expected. We may encounter higher than acceptable contaminants in our concentrates such as arsenic, mercury, selenium or other contaminants that, when present in high concentrations, can result in penalties or outright rejection of the metals concentrates by the smelters. Silver-bearing concentrates at our Sunshine Mine historically were known to contain relatively high percentages of arsenic and antimony. Accordingly, our activities may not result in profitable mining operations at the Sunshine Complex.
Our operations involve significant risks and hazards inherent to the mining industry.
Our operations involve the operation of large machines, heavy mobile equipment and drilling equipment. Hazards such as adverse environmental conditions, industrial accidents, labor disputes, unusual or unexpected geological conditions, ground control problems, cave-ins, changes in the regulatory environment, metallurgical and other processing problems, mechanical equipment failure, facility performance problems, fire and natural phenomena such as inclement weather conditions, floods and earthquakes are inherent risks in our operations. Hazards inherent to the mining industry can cause injuries or death to employees, contractors or other persons at our mineral property, severe damage to and destruction of our property, plant and equipment, and contamination of, or damage to, the environment, and can result in the suspension of our exploration activities and future development and production activities. While we aim to maintain best safety practices as part of our culture, safety measures we implement may not prevent or mitigate accidents.
In addition, from time to time, we may be subject to governmental investigations and claims and litigation filed on behalf of persons who are harmed while at our property or otherwise in connection with our operations. To the extent

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that we are subject to personal injury or other claims or lawsuits in the future, it may not be possible to predict the ultimate outcome of these claims and lawsuits due to the nature of personal injury litigation. Similarly, if we are subject to governmental investigations or proceedings, we may incur significant penalties and fines, and enforcement actions against us could result in the closing of certain of our mining operations. If claims and lawsuits or governmental investigations or proceedings are ultimately resolved against us, it could have a material adverse effect on our financial performance, financial position and results of operations. Also, if we mine on property without the appropriate licenses and approvals, we could incur liability or our operations could be suspended.
We may be materially and adversely affected by challenges relating to slope and stability of underground openings.
Our underground mines get deeper and our waste and tailings deposits increase in size as we continue and expand our mining activities, presenting certain geotechnical challenges, including the possibility of failure of underground openings. If we are required to reinforce such openings or take additional actions to prevent such a failure, we could incur additional expenses, and our operations could be negatively affected. Unexpected failures of underground openings or additional requirements to prevent such failures may adversely affect our costs and expose us to health and safety and other liabilities in the event of an accident, and in turn materially and adversely affect the results of our operations and financial condition. Additional unexpected geotechnical challenges may arise as a result of further development and construction of mines, processing facilities and related infrastructure.
The mining industry is very competitive.
The mining industry is very competitive. Much of our competition is from larger, established mining companies with greater liquidity, greater access to credit and other financial resources, newer or more efficient equipment, lower cost structures, more effective risk management policies and procedures and/or a greater ability than us to withstand losses. Our competitors may be able to respond more quickly to new laws or regulations or emerging technologies, or devote greater resources to the expansion or efficiency of their operations than we can. We also compete with other mining companies in our region for skilled labor, mining equipment and principal supplies needed for operations, any shortage of which could increase our operating costs. In addition, current and potential competitors may make strategic acquisitions or establish cooperative relationships among themselves or with third parties. Accordingly, it is possible that new competitors or alliances among current and new competitors may emerge and gain significant market share to our detriment. We may not be able to compete successfully against current and future competitors, and any failure to do so could have a material adverse effect on our business, financial condition or results of operations.
The title to some of our mineral properties may be uncertain or defective, thus risking our investment in such properties.
Certain of our mineral rights consist of “patented” and “unpatented” mining claims created and maintained in accordance with the U.S. General Mining Law of 1872 (the “ General Mining Law ”). We currently own 235 patented and 877 unpatented mining claims and lease 16 patented and 189 unpatented mining claims. Unpatented mining claims are unique U.S. property interests, and are generally considered to be subject to greater title risk than other real property interests because the validity of unpatented mining claims is often uncertain. This uncertainty arises, in part, out of the complex federal and state laws and regulations that supplement the General Mining Law. Also, unpatented mining claims and related rights, including rights to use the surface, are subject to possible challenges by third parties or contests by the federal government. The validity of an unpatented mining claim, in terms of both its location and its maintenance, is dependent on strict compliance with a complex body of federal and state statutory and decisional law. In addition, there are few public records that definitively control the issues of validity and ownership of unpatented mining claims.
The Sunshine Mine is part of the Coeur d’Alene Mining District, a historical mining district that was established prior to 1900. The history of ownership of the properties comprising the Sunshine Mine is complex and involves numerous individuals and entities. In addition, title to many of the mineralized veins at the Sunshine Mine is based on ownership of the patented claims within which those veins have their apex, as under the General Mining Law, the owner of a mining claim within which a mineralized vein has its apex owns the so-called “extralateral rights” to that vein as it may extend downward outside the vertical boundaries of the claim. As the vein extends downward, however, its actual location becomes less and less certain. As a result, ownership of these mineralized veins often becomes more a question of geology than of public records. Over the years, because of the age of the Coeur d’Alene Mining District and the existence of extralateral rights that render title to the actual minerals beneath any particular claim more uncertain, our predecessors and

### EX-5.1 - EXHIBIT 5.1
EX-5.1
3
ny20061035x5_ex5-1.htm
EXHIBIT 5.1

Exhibit 5.1

Skadden, Arps, Slate, Meagher & Flom llp

ONE MANHATTAN WEST

NEW YORK, NY 10001

TEL: (212) 735-3000

FAX: (212) 735-2000

www.skadden.com

FIRM/AFFILIATE

OFFICES

BOSTON

CHICAGO

HOUSTON

LOS ANGELES

PALO ALTO

WASHINGTON, D.C.

WILMINGTON

ABU DHABI

BEIJING

BRUSSELS

FRANKFURT

HONG KONG

LONDON

MUNICH

PARIS

SÃO PAULO

SEOUL

SINGAPORE

TOKYO

TORONTO

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May 26, 2026

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Sunshine Silver Mining & Refining Company

2209 Big Creek Rd

Kellogg, Idaho 83837

Re:

Sunshine Silver Mining & Refining Company

Registration Statement on Form S-1

Ladies and Gentlemen:

We have acted as special United States counsel to Sunshine Silver Mining & Refining Company, a Delaware corporation (the “Company”), in connection with the public offering by the Company of up to 23,000,000 shares of
common stock, par value $0.001 per share (“ Common Stock ”), of the Company (including up to 3,000,000 shares of Common Stock subject to an over-allotment option) (the “ Shares ”).

This opinion letter is being furnished in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act of 1933 (the “ Securities Act ”).

In rendering the opinion stated herein, we have examined and relied upon the following:

(a) the registration statement on Form S-1 (File No. 333-295768) of the Company relating to the Shares filed on May 11, 2026 with the Securities and Exchange Commission (the “ Commission ”) under the
Securities Act and Pre-Effective Amendment No. 1 thereto, including the information deemed to be a part of the registration statement pursuant to Rule 430A of the General Rules and Regulations under the Securities Act (the “ Rules and Regulations ”)
(such registration statement, as so amended, being hereinafter referred to as the “ Registration Statement ”);

(b) the form of the Underwriting Agreement (the “ Underwriting Agreement ”) proposed to be entered into among the Company and Morgan Stanley & Co. LLC, Scotia Capital (USA) Inc. and BMO Capital Markets
Corp., as representatives of the several Underwriters named therein (the “ Underwriters ”), relating to the sale by the Company to the Underwriters of the Shares, filed as Exhibit 1.1 to the Registration Statement;

Sunshine Silver Mining & Refining Company

May 26, 2026

Page 2

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(c) an executed copy of a certificate of Michelle Shepston, General Counsel and Secretary of the Company, dated the date hereof (the “ Secretary’s Certificate ”);

(d) a copy of the Company’s Second Amended and Restated Certificate of Incorporation certified by the Secretary of State of the State of Delaware as of May 22, 2026 (the “ Second A&R Certificate of
Incorporation ”), certified pursuant to the Secretary’s Certificate as being in effect on the date of the resolutions referred to below and as of the date hereof;

(e) a copy of the Certificate of Amendment to the Second A&R Certificate of Incorporation, certified by the Secretary of State of the State of Delaware as of May 22, 2026, and certified pursuant to the
Secretary’s Certificate as being in effect as of the date hereof;

(f) the form of the Company’s Third Amended and Restated Certificate of Incorporation, to be in effect immediately prior to the consummation of the offering of the Shares and filed as Exhibit 3.3 to the
Registration Statement (the “ Restated Certificate of Incorporation ”);

(g) a copy of the Company’s Bylaws, as certified pursuant to the Secretary’s Certificate as being in effect on the date of the resolutions referred to below and as of the date hereof;

(h) the form of the Company’s Amended and Restated Bylaws, to be in effect immediately prior to the consummation of the offering of the Shares and filed as Exhibit 3.5 to the Registration Statement (the “ Restated
Bylaws ”); and

(i) a copy of certain resolutions of the Board of Directors of the Company, adopted on May 10, 2026, certified pursuant to the Secretary’s Certificate.

We have also examined originals or copies, certified or otherwise identified to our satisfaction, of such records of the Company and such agreements, certificates and receipts of public officials, certificates of
officers or other representatives of the Company and others, and such other documents as we have deemed necessary or appropriate as a basis for the opinions stated below.

Sunshine Silver Mining & Refining Company

May 26, 2026

Page 3

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In our examination, we have assumed the genuineness of all signatures, including electronic signatures, the legal capacity and competency of all natural persons, the authenticity of all documents submitted to us as
originals, the conformity to original documents of all documents submitted to us as facsimile, electronic, certified or photocopied copies, and the authenticity of the originals of such copies. As to any facts relevant to the opinions stated herein
that we did not independently establish or verify, we have relied upon statements and representations of officers and other representatives of the Company and others and of public officials, including the facts and conclusions set forth in the
Secretary’s Certificate and the Restated Certificate of Incorporation and the factual representations and warranties set forth in the Underwriting Agreement.

We do not express any opinion with respect to the laws of any jurisdiction other than the General Corporation Law of the State of Delaware (the “DGCL”).

As used herein, “Organizational Documents” means the Restated Certificate of Incorporation and the Restated Bylaws.

Based upon the foregoing and subject to the qualifications and assumptions stated herein, we are of the opinion that:

When (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Securities Act; (ii) the Underwriting Agreement has been duly authorized,
executed and delivered by the Company and the other parties thereto; (iii) the Restated Certificate of Incorporation has been filed with the Secretary of State of the State of Delaware and has become effective; (iv) the Board of Directors of the
Company, including any appropriate committee appointed thereby, has taken all necessary corporate action to adopt the Restated Bylaws and to approve the issuance and sale of the Shares and related matters, including the price per share of the Shares;
and (v) the Shares are registered in the Company’s share registry and delivered upon payment of the consideration therefor determined by the Board of Directors, the Shares, when issued and sold in accordance with the provisions of the Underwriting
Agreement, will be duly authorized by all requisite corporate action on the part of the Company under the DGCL and validly issued, fully paid and nonassessable, provided that the consideration therefor is not less than $0.001 per Share.

In addition, in rendering the foregoing opinion we have assumed that:

(a) the Company’s issuance of the Shares does not and will not (i) except to the extent expressly stated in the opinions contained herein, violate any statute to which the Company or such issuance is subject, or
(ii) constitute a violation of, or a breach under, or require the consent or approval of any other person under, any agreement or instrument binding on the Company (except that we do not make this assumption with respect to the Organizational
Documents or those agreements or instruments expressed to be governed by the laws of the State of New York which are listed in Part II of the Registration Statement, although we have assumed compliance with any covenant, restriction or provision with
respect to financial ratios or tests or any aspect of the financial condition or results of operations of the Company contained in such agreements or instruments), and we have further assumed that the Company will continue to have sufficient
authorized shares of Common Stock; and

Sunshine Silver Mining & Refining Company

May 26, 2026

Page 4

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(b) the Company’s authorized capital stock will be as set forth in the Restated Certificate of Incorporation and we have not made any other inquiries or investigations.

This opinion letter shall be interpreted in accordance with customary practice of United States lawyers who regularly give opinions in transactions of this type.

We hereby consent to the reference to our firm under the heading “Legal Matters” in the prospectus forming part of the Registration Statement. We also hereby consent to the filing of this opinion letter with the
Commission as an exhibit to the Registration Statement. In giving this consent, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations. This
opinion letter is expressed as of the date hereof unless otherwise expressly stated, and we disclaim any undertaking to advise you of any subsequent changes in the facts stated or assumed herein or of any subsequent changes in applicable laws.

Very truly yours,

/s/ Skadden, Arps, Slate, Meagher & Flom LLP

JAW

### EX-10.17 - EXHIBIT 10.17
EX-10.17
4
ny20061035x5_ex10-17.htm
EXHIBIT 10.17

Exhibit 10.17

SUNSHINE SILVER MINING & REFINING COMPANY

AMENDED AND RESTATED

2021 LONG TERM INCENTIVE PLAN

NOTICE OF RESTRICTED STOCK UNIT GRANT

Participant Name: [Insert Name]

You (“ Participant ”) have been granted an Award of Restricted Stock Units, subject to the terms
and conditions of this Restricted Stock Unit Grant Notice (the “ Notice of Grant ”), the Sunshine Silver Mining & Refining Company Amended and Restated 2021 Long Term Incentive Plan (as
may be amended or amended and restated from time to time, the “ Plan ”) and the attached Restricted Stock Unit Agreement (the “ Award
Agreement ”), as set forth below. Unless otherwise defined herein, the terms used in this Notice of Grant shall have the meanings set forth in the Plan.

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Date of Grant:

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Number of Restricted Stock Units:

Vesting Schedule : Subject to Section 2 of the Award Agreement, the Restricted Stock Units shall vest in full on the earlier of (i) the first anniversary of the Date of Grant or (ii) the day immediately proceeding
the date of the Company’s [_______] Annual Meeting of Stockholders, subject to Participant continuing to serve as a member of the Board on the applicable vesting date. Notwithstanding any provision in this
Notice of Grant, the Award Agreement or the Plan, the Restricted Stock Units will automatically vest upon the occurrence of a Change of Control, subject to Participant continuing to serve as a member of the Board as of, or immediately prior to,
such Change of Control.

Participant Acknowledgments : By accepting this Award (whether in
writing, electronically or otherwise), Participant acknowledges and agrees to the following:

1. This Award is governed by the terms and conditions of the Award Agreement and the Plan. In the event of a conflict between the terms of the Plan and the Award Agreement, the terms of the Plan will prevail.

2. Participant has received a copy of the Plan, the Award Agreement, the Plan prospectus, and the Company’s Insider Trading Policy and represents that Participant has read these documents and is familiar with their
terms. Participant further agrees to accept as binding, conclusive, and final all decisions and interpretations of the Committee (or its delegees) (as defined in the Plan) regarding any questions relating to this Award and the Plan.

3. The Company is not providing any tax, legal, or financial advice, nor is the Company making any recommendations regarding participation in the Plan. Participant should consult with his or her own personal tax, legal,
and financial advisors regarding participation in the Plan before taking any action related to the Plan.

4. Participant consents to electronic delivery and participation as set forth in the Plan and the Award Agreement.

SUNSHINE SILVER MINING & REFINING COMPANY

By: |

Title: |

PARTICIPANT

Name:

PRIVILEGED & CONFIDENTIAL

SUNSHINE SILVER MINING & REFINING COMPANY

AMENDED AND RESTATED

2021 LONG TERM INCENTIVE PLAN

RESTRICTED STOCK UNIT AGREEMENT

1. Grant . Sunshine Silver Mining & Refining Company (the “ Company ”) has granted to the individual (“ Participant ”) named in the notice of grant (the “ Notice of Grant ”) an Award of Restricted Stock Units under the Sunshine Silver Mining & Refining Company Amended and
Restated 2021 Long Term Incentive Plan (as may be amended or amended and restated from time to time, the “ Plan ”), subject to all of the terms and conditions in the Notice of Grant, this
Restricted Stock Unit Agreement (the “ Award Agreement ”) and the Plan, which is incorporated herein by reference. If there is a conflict between the terms and conditions of the Plan and
the terms and conditions of this Award Agreement, the terms and conditions of the Plan will prevail.

2. Vesting Schedule . The Restricted Stock Units awarded by this Award Agreement will vest in accordance with the vesting provisions set forth in the Notice of Grant. Restricted Stock Units scheduled to vest on a
certain date or upon the occurrence of a certain condition will not vest in accordance with any of the provisions of this Award Agreement, unless Participant continues to serve as a member of the Board from the Date of Grant until the date such
vesting occurs.

3. Company’s Obligation to Pay .

(a) Each Restricted Stock Unit represents the right to receive a Common Share upon vesting. Unless and until the Restricted Stock Units will have vested in the manner set forth in Section 2, Participant will have no
right to receive Common Shares pursuant to any such Restricted Stock Units. Prior to the actual settlement of any vested Restricted Stock Units, such Restricted Stock Units will represent an unsecured obligation of the Company. Any Restricted
Stock Units that vest in accordance with Section 2 will be settled by delivery of whole Common Shares as set forth in this Section 3 to Participant (or in the event of Participant’s death, to his or her estate), subject to Participant satisfying
any Tax-Related Items as set forth in Section 7.

(b) Subject to the provisions of Section 4, with respect to any Restricted Stock Units that vest hereunder that are not subject to a Deferral Election (as defined below), such vested Restricted Stock Units will be
settled by delivery of whole Common Shares as soon as practicable after vesting, but in each such case within the period ending no later than the date that is two and one-half (2½) months from the end of the Company’s tax year that includes the
vesting date.

(c) Subject to the provisions of Section 4, with respect to any Restricted Stock Units that vest hereunder and are subject to a validly made election to defer the settlement of the Common Shares upon vesting on a form
and by the deadline provided by the Company (a “ Deferral Election ”), such vested Restricted Stock Units will be settled by delivery of whole Common Shares within thirty (30) calendar days following such
designated payment date set forth in the Deferral Election; provided, however, in the event the Restricted Stock Units vest upon a Change of Control that qualifies as a “change in control event” within the meaning of Code Section 409A, then
notwithstanding any Deferral Election the Restricted Stock Units will be settled by delivery of whole Common Shares within thirty (30) calendar days following such Change of Control.

4. Section 409A Compliance . It is the intent of this Award Agreement that it and all payments and benefits hereunder be exempt from, or comply with, the requirements of Code Section 409A so that none of the
Restricted Stock Units provided under this Award Agreement or Common Shares issuable thereunder will be subject to the additional tax imposed under Code Section 409A, and any ambiguities herein will be interpreted to be so exempt or to comply. In
no event will Participant be permitted, directly or indirectly, to specify the taxable year in which Common Shares will be issued upon settlement of any Restricted Stock Units under this Award Agreement. Each payment payable under this Award
Agreement is intended to constitute a separate payment for purposes of U.S. Treasury Regulation Section 1.409A-2(b)(2). The Company makes no representation that any or all of the payments and benefits under this Award Agreement comply with Code
Section 409A and makes no undertaking to preclude Code Section 409A from applying to any such payments or benefits. Participant shall be solely responsible for the payment of any taxes and penalties incurred under Code Section 409A. For purposes
of this Award Agreement, “Code Section 409A” means Section 409A of the Code, and any final U.S. Treasury Regulations and U.S. Internal Revenue Service guidance thereunder, as each may be amended from time to time.

5. Forfeiture upon Termination of Service . Any Restricted Stock Units that have not vested will be forfeited and will return to the Plan on the date following the termination of Participant’s membership on the
Board.

6. Death of Participant . Any distribution or delivery to be made to Participant under this Award Agreement will, if Participant is then deceased, be made to Participant’s designated beneficiary, if so allowed by
the Committee in its sole discretion, or if no beneficiary survives Participant, the administrator or executor of Participant’s estate. Any such transferee must furnish the Company with (a) written notice of his or her status as transferee, and (b)
evidence satisfactory to the Company to establish the validity of the transfer and compliance with any applicable laws or regulations pertaining to said transfer.

7. Withholding of Taxes . Regardless of any action the Company or a Subsidiary takes with respect to any or all applicable national, local, or other tax or social contribution, withholding, required deductions, or
other payments, if any, that arise upon the grant or vesting of the Restricted Stock Units or the holding or subsequent sale of Common Shares, and the receipt of dividends, if any, or otherwise in connection with the Restricted Stock Units or the
Common Shares (“ Tax-Related Items ”), Participant acknowledges and agrees that the ultimate liability for all Tax-Related Items legally due by Participant is and remains Participant’s
responsibility and may exceed any amount actually withheld by the Company or a Subsidiary. Participant further acknowledges that the Company and a Subsidiary (a) make no representations or undertakings regarding the treatment of any Tax-Related
Items in connection with any aspect of the Restricted Stock Units, including the grant, vesting or settlement of the Restricted Stock Units, the subsequent sale of Common Shares acquired under the Plan, and the receipt of dividends, if any; and (b)
do not commit to and are under no obligation to structure the terms of the Restricted Stock Units or any aspect of the Restricted Stock Units to reduce or eliminate Participant’s liability for Tax-Related Items, or achieve any particular tax
result.

-2-

As a condition to the grant and vesting of the Restricted Stock Units and as set forth in Section 16 of the Plan, Participant hereby agrees to make
adequate provision for the satisfaction of (and will indemnify the Company and any Subsidiary for) any Tax-Related Items. In this regard, the Company and/or any Subsidiary shall have the right to satisfy the obligations with regard to any Tax-Related
Items by one or a combination of the following: (i) by receipt of a cash payment from Participant; (ii) by withholding from Participant’s wages or other cash compensation paid to Participant by the Company or any Subsidiary; (iii) by withholding
Common Shares that otherwise would be issued to Participant upon payment of the vested Restricted Stock Units; (iv) by withholding from proceeds of the sale of Common Shares acquired upon payment of the vested Restricted Stock Units through a
voluntary sale or a mandatory sale arranged by the Company (on Participant’s behalf pursuant to this authorization), or (v) by any other arrangement approved by the Committee. Any Common Shares withheld pursuant to this Section 7 shall be valued
based on the Fair Market Value as of the date the withholding obligations are satisfied. Furthermore, Participant agrees to pay the Company or any Subsidiary any Tax-Related Items that cannot be satisfied by the foregoing methods. Any fraction of a
Common Share which would be required to satisfy such an obligation shall be disregarded and the remaining amount due shall be paid in cash by Participant.

8. Rights as Stockholder . Neither Participant nor any person claiming under or through Participant will have any of the rights or privileges of a stockholder of the Company in respect of any Common Shares
deliverable hereunder unless and until such Common Shares will have been issued (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company). After such issuance, Participant will have
all the rights of a stockholder of the Company with respect to voting such Common Shares and receipt of dividends and distributions on such Common Shares, but prior to such issuance, Participant will not have any rights to dividends and/or
distributions on such Common Shares.

9. No Guarantee of Future Grants . Participant acknowledges and agrees that: (a) the Plan is established voluntarily by the Company, it is discretionary in nature and it may be modified, amended, suspended or
terminated by the Company at any time; (b) the grant of Restricted Stock Units is voluntary and occasional and does not create any contractual or other right to receive future grants of Restricted Stock Units, or benefits in lieu of Restricted
Stock Units even if Restricted Stock Units have been granted repeatedly in the past; (c) all decisions with respect to future awards of Restricted Stock Units, if any, will be at the sole discretion of the Company; (d) Participant’s participation
in the Plan is voluntary; (e) the Restricted Stock Units and the Common Shares subject to the Restricted Stock Units are extraordinary items that do not constitute regular compensation for services rendered to the Company or any Subsidiary, and
that are outside the scope of Participant’s employment contract, if any; (f) the Restricted Stock Units and the Common Shares subject to the Restricted Stock Units are not intended to replace any pension rights or compensation; (g) the Restricted
Stock Units and the Common Shares subject to the Restricted Stock Units are not part of normal or expected compensation or salary for any purposes, including, but not limited to, calculating any severance, resignation, termination, redundancy,
dismissal, or end of service payments, bonuses, long-service awards, pension or retirement or welfare benefits or similar payments and in no event should be considered as compensation for, or relating in any way to, past services for the Company or
any Subsidiary, subject to applicable laws.

-3-

10. Address for Notices . Any notice to be given to the Company under the terms of this Award Agreement will be addressed to the Company, in care of an individual determined by the Committee from time to time, at
such address that may be notified to the recipient in writing from time to time, or at such other address as the Company may hereafter designate in writing.

11. Grant is Not Transferable . Except to the limited extent provided in Section 6, this grant and the rights and privileges conferred hereby may not be transferred, assigned, pledged or hypothecated in any way
(whether by operation of applicable laws or otherwise) and may not be subject to sale under execution, attachment or similar process. Upon any attempt to transfer, assign, pledge, hypothecate or otherwise dispose of this grant, or any right or
privilege conferred hereby, or upon any attempted sale under any execution, attachment or similar process, this grant and the rights and privileges conferred hereby immediately will become null and void.

12. Binding Agreement . Subject to the limitation on the transferability of this grant contained herein, this Award Agreement will be binding upon and inure to the benefit of the heirs, legatees, legal
representatives, successors and assigns of the parties hereto.

13. Additional Conditions to Issuance of Common Shares and Imposition of Other Requirements . If at any time the Company will determine, in its discretion, that the listing, registration, qualification or
compliance of the Common Shares upon or with any securities exchange or under any applicable laws, the tax code and related regulations or the consent or approval of any governmental regulatory authority is necessary or desirable as a condition to
the issuance of Common Shares to Participant (or his or her estate) hereunder, such issuance will not occur unless and until such listing, registration, qualification, compliance, consent or approval will have been completed, effected or obtained
free of any conditions not acceptable to the Company. Where the Company determines that the delivery of any Common Shares will violate any state, federal or foreign securities or exchange laws or other applicable laws, the Company will defer
delivery until the earliest date at which the Company reasonably anticipates that the delivery of Common Shares will no longer cause such violation. The Company will make all reasonable efforts to meet the requirements of any applicable laws or
securities exchange and to obtain any such consent or approval of any such governmental authority or securities exchange. The Company shall not be obligated to issue any Common Shares pursuant to the Restricted Stock Units at any time if the
issuance of Common Shares violates or is not in compliance with any applicable laws.

Furthermore, the Company reserves the right to impose other requirements on Participant’s participation in the Plan, on the Restricted Stock Units and on
any Common Shares acquired under the Plan, to the extent the Company determines it is necessary or advisable in order to comply with any applicable laws or facilitate the administration of the Plan, and to require Participant to sign any additional
agreements or undertakings that may be necessary to accomplish the foregoing. Furthermore, Participant understands that the applicable laws of the country in which he or she is resident at the time of grant or vesting of the Restricted Stock Units
or the holding or disposition of Common Shares (including any rules or regulations governing securities, foreign exchange, tax, labor or other matters) may restrict or prevent the issuance of Common Shares or may subject Participant to additional
procedural or regulatory requirements he or she is solely responsible for and will have to independently fulfill in relation to the Restricted Stock Units or the Common Shares. Participant also understands and agrees that if Participant works,
resides, moves to, or otherwise is or becomes subject to applicable laws or company policies of another jurisdiction at any time, certain country-specific notices, disclaimers and/or terms and conditions may apply to him as from the date of grant,
unless otherwise determined by the Company in its sole discretion.

-4-

14. Plan Governs . This Award Agreement is subject to all terms and provisions of the Plan. If there is a conflict between one or more provisions of this Award Agreement and one or more provisions of the Plan,
the provisions of the Plan will govern. Capitalized terms used and not defined in this Award Agreement will have the meaning set forth in the Plan.

15. Electronic Delivery and Acceptance . By accepting this Award, Participant agrees to participate in the Plan through an on-line or electronic system established and maintained by the Company or a third party
designated by the Company, and consents to the electronic delivery of the Award Agreement, the Plan, account statements, Plan prospectuses, and all other documents, communications, or information related to the Award and current or future
participation in the Plan. Electronic delivery may include the delivery of a link to the Company intranet or the internet site of a third party involved in administering the Plan, the delivery of the document via e-mail, or such other delivery
determined at the Company’s discretion. Participant may receive from the Company a paper copy of any documents delivered electronically at no cost if Participant contacts the Company by telephone, through a postal service, or electronic mail at an
address that may be notified to Participant in writing from time to time.

16. Translation . If Participant has received this Award Agreement, including appendices, or any other document related to the Plan translated into a language other than English, and the meaning of the translated
version is different than the English version, the English version will control.

17. Captions . Captions provided herein are for convenience only and are not to serve as a basis for interpretation or construction of this Award Agreement.

18. Agreement Severable . If any provision in this Award Agreement will be held invalid or unenforceable, such provision will be severable from, and such invalidity or unenforceability will not be construed to
have any effect on, the remaining provisions of this Award Agreement.

19. Modifications to the Award Agreement . This Award Agreement constitutes the entire understanding of the parties on the subjects covered. Participant expressly warrants that he or she is not accepting this
Award Agreement in reliance on any promises, representations, or inducements other than those contained herein. Modifications to this Award Agreement or the Plan can be made only in an express written contract executed by a duly authorized officer
of the Company. Notwithstanding anything to the contrary in the Plan or this Award Agreement, the Company reserves the right to revise this Award Agreement as it deems necessary or advisable, in its sole discretion and without the consent of
Participant, to comply with Code Section 409A or to otherwise avoid imposition of any additional tax or income recognition under Code Section 409A in connection with this Award of Restricted Stock Units.

-5-

20. Data Privacy . Participant hereby explicitly and unambiguously consents to the collection, use and transfer, in electronic or other form, of Participant’s
Personal Data (as described below) by and among, as applicable, the Company, any Subsidiary, or affiliate, or third parties as may be selected by the Company for the exclusive purpose of implementing, administering and managing Participant’s
participation in the Plan. Participant understands that refusal or withdrawal of consent will affect Participant’s ability to participate in the Plan; without providing consent, Participant will not be able to participate in the Plan or realize
benefits (if any) from the Restricted Stock Units.

Participant understands that the Company and any Subsidiary, affiliate, or designated third parties may hold
personal information about Participant, including, but not limited to, Participant’s name, home address and telephone number, date of birth, social insurance number or other identification number, salary, nationality, job title, any shares of stock
or directorships held in the Company or any Subsidiary, or affiliate, details of all Restricted Stock Units or any other entitlement to Common Shares awarded, canceled, exercised, vested, unvested or outstanding in Participant’s favor (“Personal
Data”). Participant understands that Personal Data may be transferred to any Subsidiary, affiliate, or third parties assisting in the implementation, administration and management of the Plan, that these recipients may be located in the United
States, Participant’s country (if different than the United States), or elsewhere, and that the recipient’s country may have different data privacy laws and protections than Participant’s country. In particular, the Company may transfer Personal
Data to the broker or stock plan administrator assisting with the Plan, to its legal counsel and tax/accounting advisor, and to the affiliate or entity that is Participant’s employer and its payroll provider.

21. Foreign Exchange Fluctuations and Restrictions . Participant understands and agrees that the future value of the underlying Common Shares is unknown and cannot be predicted with certainty and may decrease.
Participant also understands that neither the Company, nor any affiliate is responsible for any foreign exchange fluctuation between local currency and the United States Dollar or the selection by the Company or any affiliate in its sole discretion
of an applicable foreign currency exchange rate that may affect the value of the Restricted Stock Units or Common Shares received (or the calculation of income or Tax-Related Items thereunder). Participant understands and agrees that any
cross-border remittance made to transfer proceeds received upon the sale of Common Shares must be made through a locally authorized financial institution or registered foreign exchange agency and may require Participant to provide such entity with
certain information regarding the transaction.

22. Amendment, Suspension or Termination of the Plan . By accepting this Award, Participant expressly warrants that he or she has received an Award of Restricted Stock Units under the Plan, and has received, read
and understood a description of the Plan. Participant understands that the Plan is discretionary in nature and may be amended, suspended or terminated by the Company at any time.

23. Governing Law . This Award Agreement will be governed by the laws of the State of Delaware, without giving effect to the conflict of law principles thereof.

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### EX-23.1 - EXHIBIT 23.1
EX-23.1
5
ny20061035x5_ex23-1.htm
EXHIBIT 23.1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the reference to our firm under the caption "Experts" and to the use of our report dated April 3, 2026 (except Note 18, as to which the date
is May 11, 2026), in Amendment No. 1 to the Registration Statement (Form S-1 No. 333-295768) and related Prospectus of Sunshine Silver Mining & Refining Company for the registration of shares of its common stock.

/s/ Ernst & Young LLP

Denver, Colorado

May 26, 2026

### EX-FILING FEES - FILING FEES TABLE
Exhibit 107

CALCULATION OF FILING FEE TABLE

Form S-1

(Form Type)

Sunshine Silver Mining & Refining Company

(Exact Name of Registrant as Specified in its Charter)

Table 1: Newly Registered Securities

| |
(1)
| (1.a.) Includes the aggregate offering price of additional shares that the underwriters have the option to purchase to cover over-allotments, if any.
(1.b.) Estimated solely for the purpose of calculating the registration fee in accordance with Rule 457(a) under the Securities Act of 1933, as amended.
|

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(2)

See Note 1.

0002091017

2026-05-26
2026-05-26

0002091017

2026-05-26
2026-05-26

xbrli:shares

iso4217:USD

xbrli:shares

iso4217:USD

xbrli:pure