US-based exploration mining company Texas Wyoming Drilling’s (TWDL’s) unexpected platinum deposits discovery at its Blue Jacket gold mine in Idaho, in the US, could make it only the second miner in the US to produce viable amounts of platinum-group metals (PGMs).

The company reported late last year that after ore sample analysis and metallurgical assay, it could confirm the presence of an estimated 2.602 oz/t of platinum.

The size of the deposit is not yet fully known, while the only other viable US platinum mining operation is the Stillwater Mining Company’s Stillwater and East Boulder mines, in Montana.

The Stillwater mine has been producing PGMs since 1986 after feasibility and baseline studies for the palladium-rich J-M reef was identified there in the 1970s.

Initial construction of the mine was completed by 1986 when underground mining started. Since 1998, it has been producing over 400 000 oz/y of palladium and platinum.

In addition, the company’s East Boulder mine was initially permitted in 1992, with two 3.5-mile-long portals bored to access the ore in 1999.

Most of the major above-ground facilities and infrastructure were completed in 2000, and in 2002, it produced 125 000 oz of palladium and platinum.

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