A view of the Stibnite project pit.
The launch followed Perpetua’s posting of $139 million in financial assurance and confirmation from the US Forest Service (USFS) that all pre-construction requirements were satisfied. The USFS issued its record of decision in January and provided final federal approval in May.
“Today, we break ground on the Stibnite gold project,” said CEO Jon Cherry. “As America’s answer to China’s antimony export bans, we are focused on swiftly and safely bringing our antimony and gold project into development.” He noted that after nine years of permitting, the project will both supply essential minerals and rehabilitate an abandoned mining site. “With our reclamation performance bond to reclaim the work we undertake at the project site in place, we officially started early works construction today and are making good on our promises to Idaho and America,” he added.
The Stibnite project is designed to produce approximately 450,000 ounces of gold annually, backed by proven and probable reserves of 148 million pounds of antimony and more than 6 million ounces of gold. It is the only identified domestic source of antimony, a mineral used in defence systems, energy storage, and semiconductors, and one of the largest deposits outside China.
According to the 2023 US Geological Survey, Stibnite could provide around 35% of the United States’ antimony demand during its first six years of operation. The project is expected to be among the country’s highest-grade open-pit gold mines, averaging 450,000 ounces of annual gold production in its initial four years. Perpetua plans to create roughly 950 direct jobs during construction and 550 during operations.
The company is also advancing financing discussions, with preliminary support from the US Export-Import Bank’s Make More in America and China Transformational Export programs. The proposed financing package includes up to $2 billion in debt funding, with final board review anticipated in spring 2026.
Perpetua stated that the final mine plan was adjusted to reduce the project footprint by 13%, enhance stream and wetland conditions, and reconnect fish habitats. The company pledged to repair legacy environmental impacts from previous mining operations in Idaho’s Stibnite-Yellow Pine district, located about 222 kilometres northeast of Boise.
Despite these commitments, the Nez Perce Tribe has expressed opposition to the project, citing potential risks to salmon populations and downstream ecosystems. The site was an important antimony source during World War II and currently holds 104.6 million proven and probable tonnes grading 1.43 grams of gold per tonne and 0.064% antimony, containing an estimated 4.8 million ounces of gold and 148 million pounds of antimony.
