Red Mountain Mining Ltd (ASX:RMX) has outlined further progress across its expanding US critical minerals portfolio, highlighting high-grade antimony sampling at its newly acquired Thompson Falls project in Montana and advancing exploration plans across Utah and Idaho.
At Thompson Falls, just 4.2 kilometres from United States Antimony Corporation’s operating smelter — the only active antimony smelter in the US — initial rock chip sampling from historical workings returned grades of up to 36.5% antimony and 0.65 g/t gold. The program identified three historical underground mines and an open pit within the project area. Further assay results are due by late February, with a comprehensive surface mapping and sampling campaign scheduled to begin in March, alongside plans for high-resolution geophysical surveys to refine drill targets.
In Utah, Red Mountain’s Antimony Project adjoins American Tungsten and Antimony’s Antimony Canyon Project, which hosts a conceptual exploration target of 12.8 million–15.6 million tonnes at 0.75–1.5% Sb. Recent reports of visible stibnite mineralisation between the two projects support potential strike extensions into Red Mountain’s ground.
The company also holds the Yellow Pine and Silver Dollar projects in Idaho, near Perpetua Resources’ Stibnite gold-antimony development, and ended the quarter with $2.18 million in cash.