June 2024

Perpetua Resources’ proposed gold and antimony mine is located in the Stibnite Mining District about 40 air miles east of McCall.Perpetua, formerly known as Midas Gold, hopes to extract about $6 billion in gold and other minerals from Stibnite, the site of historic mining operations during World War II and as far back as 1899.The Boise company’s original mining proposal was submitted in 2016 and is currently being reviewed by the Payette National Forest, the lead permitting agency.Approval of the project would trigger a three-year construction phase that Perpetua estimates would cost about $1.26 billion, followed by 12 to 15 years of mining.Gold, silver, and antimony would be extracted from three open pit mines totaling about 473 acres of disturbance within the 1,740-acre project zone, which is about three miles from the Frank Church – River of No Return Wilderness.An on-site ore processing facility would remove gold and silver from up to 25,000 tons of rock per day in a contained cyanide circuit, according to Perpetua’s operating plan.The mine is expected to produce 115 million pounds of antimony and 4.2 million ounces of gold, which is expected to account for 94% of the mine’s estimated $6 billion in lifetime revenue.Stibnite would become the only domestic mined source of antimony and would supply an estimated 30% of the annual demand for the mineral in the United States, according to Perpetua.Antimony is used in the renewable energy industry and to make flame-proofing materials, paint, glass, defense munitions and ceramics.Exploration of the Stibnite Mining District began with drilling in 2009.