US Antimony restarts Early at Stibnite Hill

The United States Antimony Corporation has officially informed that it has resumed operations at its Stibnite Hill site in Thompson Falls, Montana, marking an earlier-than-expected restart following a milder winter season. After suspending activities last November due to harsh weather conditions, the company has leveraged favorable climate patterns and low snowfall to accelerate its return to production.

Restart

This restart builds on last year’s operational momentum, when more than 800 tonnes of antimony ore were transported within just two months to the Radersburg Flotation Facility for processing. The resulting concentrate continues its journey to the Thompson Falls smelter, where it is refined into finished products supplied to customers.

Refining mining strategy

Looking ahead, USAC is refining its mining and environmental strategy. Current efforts include improved land management practices, where smaller vegetation is processed into mulch to accelerate revegetation and support reclamation goals. At the same time, the company is investing in precision mapping, with survey teams deploying GPS-based base stations across surrounding mountain terrain. This approach enhances the accuracy of identifying antimony vein structures, enabling better projections of their orientation and depth while also supporting more effective delineation of disturbed areas for reclamation planning.

Broader strategic developments

The operational restart aligns with broader strategic developments at both the company and national level. Recently, USAC secured $27 million in funding under Title III of the Defense Production Act, aimed at strengthening domestic supply chains for critical minerals. This initiative forms part of a wider push by the US government, reinforced through Executive Order 14241, to increase domestic production capacity for strategic resources.

Further underscoring the importance of antimony in national security, USAC was awarded a contract in September 2025 worth up to $245 million by the Defense Logistics Agency. The agreement covers the supply of antimony metal ingots to the national defense stockpile over the next five years.

Altogether, these developments highlight a growing convergence between mining operations, technological optimization, environmental responsibility, and geopolitical priorities, positioning antimony as a key material in the evolving landscape of critical mineral security.