Sunshine Silver Mining & Refining to Begin Trading on NYSE

KELLOGG, Idaho, June 4, 2026 /PRNewswire/ -- Sunshine Silver Mining & Refining Company (the "Company" or "Sunshine") will begin trading today on the New York Stock Exchange ("NYSE") under the ticker symbol "SSMR."

Dr. Thomas S. Kaplan, Chairman, Sunshine Silver Mining & Refining Company: "Today marks the beginning of a new chapter for the iconic Sunshine Mine and the United States' silver production. Sunshine is a truly differentiated, superlative-rich asset, bringing together attributes that matter the most in this market: exceptional grade and scale, excellent exploration targets, a premier U.S. jurisdiction, substantial existing infrastructure, and a clear path toward restarting production. At a time when silver demand is rising across solar, electrification, electronics and advanced technologies, while primary silver supply remains constrained, Sunshine offers investors exposure to a scarce, U.S.-based pure-play silver asset with vertically integrated refining operations that have the potential to produce 99.99 silver bars eligible for the COMEX as well as antimony metal. With both metals having been declared to be critical minerals by both the United States and China, we believe this autonomy away from geopolitics to be a significant advantage."

Sunshine owns and controls the Sunshine Mine, one of the highest-grade pure-play silver resources in the world. The Sunshine Mine has an average diluted silver grade of 1,022 grams per tonne in Indicated Mineral Resources,¹ approximately three-times the grade of other high-grade silver assets globally.² It hosts 103.9 million ounces of silver Indicated Mineral Resources and 159.8 million ounces of silver Inferred Mineral Resources.³

Once in production, the Sunshine Mine is expected to produce approximately 6.7 million ounces of silver annually in its first five years of production with 5.8 million ounces over a 24-year mine life,³ which would make it the second largest primary silver mine in the U.S.⁴ It is also one of the few vertically integrated, permitted mine-to-mill-to-refinery platforms in the U.S., with potential on-site production of silver and antimony.

Sunshine has the potential to be a critical minerals hub. Historically, the Sunshine Mine contained economic quantities of antimony, producing over 48.4 million pounds of finished antimony between 1953 and 2001. The Company is currently evaluating the design and engineering for the already permitted Sunshine Antimony Plant, which, including Sunshine's own byproduct antimony production could potentially produce up to 34.5 million pounds of finished antimony annually⁵ – supplying up to 60% of U.S. demand for this critical mineral.⁶

Heather White, CEO, Sunshine Silver Mining and Refining Company: "With our having a clear path to the revitalization and restart of the Sunshine Mine, Sunshine's NYSE listing represents an important step as we move toward execution. Our near-term focus is on completing infill drilling and engineering designs to support a Feasibility Study for the Sunshine Mine, currently targeted for completion in early 2027. From there, we plan to begin mill construction and complete infrastructure upgrades, with the goal of delivering silver production in late 2028."

"Sunshine benefits from a significant head start. The Sunshine Mine has permits in-hand, substantial existing infrastructure estimated to be worth $600 million, and the multiple benefits of $208 million of investments made over the last 16 years to explore, maintain, and modernize the asset. This foundation is expected to reduce both timeline and execution risk as we work to bring the historic Sunshine Mine back into production."

About Sunshine Silver Mining & Refining Company

The Company is dedicated to bringing the historic, permitted Sunshine Mine back into production. As the largest mineral rights holder in Idaho's Coeur d'Alene Mining District – the most prolific silver district in U.S. history – Sunshine benefits from favorable mining regulations, an existing skilled labor force, mine suppliers and strong support for mining from the local population and government. The Sunshine Mine is one of the highest-grade primary silver resources in the world, and the Company is one of the few U.S.-based entities with a vertically integrated mine-to-mill-to-refinery platform, supported by a permitted onsite silver refinery and the major permits required for antimony production.

Citations

^[1,3] Mineral resource estimates are based on the Company's technical report summary for the Sunshine Mine, filed as an exhibit to the Company's Registration Statement on Form S-1. For additional information and a copy of the technical report, visit: https://sunshinesilvermining.com/sunshine-mine/.
^[2] Based on the median grades of the top fifteen highest grade silver assets globally, excluding Russia, of assets with contained Measured and Indicated Mineral Resources of at least 45 million ounces of silver and Inferred Mineral Resources of at least 5 million ounces of silver.
^[4] Based on the Silver Institute's "World Silver Survey 2025" report.
^[5] Assumes antimony facility runs at 100% capacity, producing 34.5 Mlbs antimony annually.
^[6] Estimated U.S. market demand as of 2030, as provided by the Argus Report.

Forward-Looking Statements

This press release contains forward-looking statements, including statements regarding the Company's business strategy, the Company's plans and objectives for future operations and industry trends. These statements are not historical facts but rather are based on the Company's current expectations and projections regarding its business, operations and other factors relating thereto. Words such as "may," "might," "could," "would," "achieve," "budget," "scheduled," "forecasts," "should," "expects," "plans," "anticipates," "believes," "estimates," "predicts," "potential" or "continue" and similar expressions are used to identify these forward-looking statements. All forward-looking statements speak only as of the date on which they are made. These statements are not guarantees of future performance and involve certain risks, uncertainties and assumptions concerning future events that are difficult to predict. Therefore, actual future events or results may differ materially from these statements. We caution you not to place undue reliance on these forward-looking statements.

SOURCE Sunshine Silver Mining & Refining