United States Antimony Corporation Announces Today "Wet Commissioning" of Its Radersburg Flotation Mill

DALLAS, July 7, 2026 (Newswire.com) - United States Antimony Corporation ("USAC," "U.S. Antimony," or the "Company"), (NYSE American:UAMY)(NYSE Texas:UAMY), a leading producer and processor of antimony, zeolite, and other critical minerals, and the only fully integrated antimony company in the world outside of China and Russia, is pleased to announce today the wet commissioning of its critical mineral flotation mill located in Radersburg, Montana.

The Company will celebrate this significant milestone with a Rock Breaking and Ribbon Cutting Ceremony today, July 7, 2026, from 11:00 a.m. to 2:00 p.m. MST at 161 Keating Gulch Road, Radersburg, Montana, with the Governor of Montana in attendance. Following the $4.75 million acquisition of this facility in January of this year and the subsequent ~$2 million capital expenditures for specific equipment upgrades, refurbishments, and a new laboratory, the facility is now ready to come online and process the initial ~800 tons of antimony ore mined last fall from the Company's Stibnite Hill operations in Thompson Falls, Montana.

The Radersburg Flotation Mill will start production once the laboratory is fully commissioned to allow for process and product control. The ~$1 million cost to build a new laboratory features full sample preparation, a 3-kilowatt XRF, fire assay, and wet chemistry capabilities with all newly acquired equipment. Full commissioning of the laboratory and subsequent concentrate production from the mill is planned for some time in mid-July. The Stibnite Hill mine is currently producing raw antimony ore for future processing. This midstream asset is a cornerstone in USAC's fully vertical integration strategy, enabling the Company to upgrade antimony-bearing material from its Montana and Alaska mining operations into high-grade concentrate suitable for downstream smelting allowing antimony metal, trioxide, and trisulfide production. This additional throughput will enhance USAC's ability to fulfill its $245 million, sole-source Department of War contract for Military Specification ("MIL-SPEC") antimony metal, as well as its commercial obligations for fire retardants and other products, at an accelerated pace.

USAC'S INTEGRATED OPERATIONS

USAC's operating business consists of three critical stages:

• Stage 1 - Mining: Extraction of raw antimony ore (primarily stibnite) meeting strict specifications of ≥10% Sb with minimal impurities.

• Stage 2 - Concentration via Flotation (Radersburg): Midstream beneficiation that produces a high-grade ~60% Sb concentrate through gravity and flotation circuits. This step is essential but requires specification-compliant feedstock before going to the third phase, smeltering operations.

• Stage 3 - Smelting (Thompson Falls and Mexico): Oxidation and reduction smelting that removes remaining impurities to produce finished high-purity antimony products (metal, trioxide, trisulfide, etc.).

The Radersburg flotation facility was USAC's missing piece in its fully integrated, 100% Company-owned portfolio of production equipment and facilities as its previous flotation facility was under lease from a third-party. It now provides the Company with an in-house, fully permitted, and operational midstream concentration facility located within the State of Montana, which dramatically strengthens control over our supply chain and completely eliminating reliance on third-party mills, which are unreliable, expensive, and out of date.

Current Process Limitations and the Path Forward with Hydromet

China's export restrictions beginning in September 2024 triggered a historic supply shock and price surge that reached over 500%, making it economical for artisanal and small-scale miners worldwide to ramp up production. However, the overwhelming majority of this new global supply does not and cannot meet the tight specifications required for pyrometallurgical smelting. Flotation processes can be used to produce concentrates with these stringent specifications, if the inherent mineralogy is conducive, by rejecting minerals that carry diluents such as arsenic, lead, and iron. Some refractory ores do not yield to this level of separation. To overcome these limitations and unlock far greater volumes of domestic and international feedstock, USAC has submitted a direct application in January 2026 to the U.S. Department of Energy (DOE) in support of an estimated $44 million build cost Hydrometallurgical ("Hydromet") Refinery with Critical Materials Byproduct Recovery project at the already-permitted Radersburg site ($35.2 million requested in U.S. government funds). This next-generation Hydromet platform would accept a much wider range of antimony-bearing materials, deliver cleaner processing with higher recovery rates, enable byproduct recovery of other critical minerals, reduce environmental footprint, and support significantly higher production volumes.

Spot Antimony Pricing

Traditional Western spot-pricing benchmarks, including assessments for material in Rotterdam reported by Argus Media and other leading sources, fundamentally miss this key distinction. While an antimony market has clearly emerged, current published antimony pricing does not accurately reflect the true scarcity of usable, specification-compliant material capable of producing MIL-SPEC products. If the broader market fully understood and priced in the significant issues around acceptable feedstock quality and processing requirements, the realized commodity price would be substantially higher than it is today. This market inefficiency is exactly why USAC believes North America should develop its own dedicated pricing index in collaboration with domestic producers of critical minerals such as antimony. A North American index would provide greater transparency, better reflect the economics of secure high-specification supply, and help establish appropriate floor pricing that allows American companies to invest, expand, and succeed in this strategically essential sector.

Commenting on the Radersburg milestone announced today, Mr. Gary C. Evans, Chairman and CEO of USAC stated, "The commissioning of our Radersburg flotation facility represents another transformative step in building a secure, fully integrated domestic antimony supply chain. After targeted upgrades, we are now ready to begin the process of material from our own Montana operations and celebrate this achievement with a ribbon cutting ceremony today with Governor Greg Gianforte, a key supporter of all of our initiatives in the great state of Montana. We were honored to also have the Governor tour our Thompson Falls Stibnite Hill mine and Smelter last year. This midstream asset at Radersburg was the only missing piece of our vertical integration plan. Looking ahead, the potential Hydromet facility at this permitted site will fundamentally change what we can process, moving beyond today's strict grade and impurity limits to accept a broader spectrum of antimony-bearing ores from around the world. Assuming all of our current growth objectives are met over the next several years, we believe USAC is positioned to deliver 50% of product to the US market. In a market reshaped by global supply disruptions and surging demand from defense, energy, and technology sectors, management and our board has positioned USAC to deliver reliable, high-quality supply at scale others cannot match for years to come."

About USAC:

United States Antimony Corporation and its subsidiaries in the U.S., Mexico, and Canada ("USAC," "U.S. Antimony," the "Company," "Our," "Us," or "We") sell antimony, zeolite, and precious metals primarily in the U.S., Mexico, and Canada. The Company mines, purchases, and processes ore primarily into antimony oxide, antimony metal, antimony trisulfide, and precious metals at its facilities located in Montana and Mexico. Antimony oxide is used to form a flame-retardant system for plastics, rubber, fiberglass, textile goods, paints, coatings, and paper, as a color fastener in paint, and as a phosphorescent agent in fluorescent light bulbs. Antimony metal is used in bearings, storage batteries, and ordnance. Antimony trisulfide is used as a primer in ammunition. The Company also recovers precious metals, primarily gold and silver, at its Montana facility from third party ore. At its Bear River Zeolite ("BRZ") facility located in Idaho, the Company mines and processes zeolite, a group of industrial minerals used in water filtration, sewage treatment, nuclear waste and other environmental cleanup, odor control, gas separation, animal nutrition, soil amendment and fertilizer, and other miscellaneous applications. Beginning in 2024 and continuing in 2025, the Company acquired mining claims, real properties (patented claims) and leases located in Alaska, Montana, and Ontario, Canada in an effort to reduce the cost of third-party antimony ore purchases and to expand its product offerings.

Learn more about United States Antimony Corporation at www.usantimony.com.

Forward-Looking Statements:

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, without limitation, statements regarding the Company's future operations, production levels, financial performance, business strategy, market conditions, demand for antimony, zeolite, other critical minerals, and precious metals, expected costs, and other statements that are not historical facts. These statements are based on current expectations, estimates, forecasts, and projections about the industries in which the Company operates, as well as management's beliefs and assumptions. Words such as "anticipates," "expects," "intends," "plans," "believes," "seeks," "estimates," "may," "will," "should," "could," and variations of these words or similar expressions are intended to identify such forward-looking statements.

Forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those indicated in such statements, including, but not limited to: fluctuations in the market prices and demand for antimony and zeolite; changes in domestic and global economic conditions; operational risks inherent in mining and mineral processing; geological or metallurgical conditions; availability and cost of energy, equipment, transportation, and labor; the Company's ability to maintain or obtain permits, licenses, and regulatory approvals; changes in environmental and mining laws or regulations; competitive factors; the impact of geopolitical developments; and the effects of weather, natural disasters, or health pandemics on operations and supply chains. Additional information regarding risk factors that could cause actual results to differ materially is included in the Company's filings with the U.S. Securities and Exchange Commission, including its Annual Report on Form 10-K and Quarterly Reports on Form 10-Q.

The Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise, except as required by law. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.

SOURCE: United States Antimony Corp.

Source: United States Antimony Corp.