A new front in America’s push to break dependence on foreign critical minerals opened this week as Perpetua Resources, the U.S. Army and Idaho National Laboratory launched a pilot plant designed to advance a domestic supply chain for military-grade antimony.

 

The modular mineral processing facility, located at Idaho National Laboratory in Idaho Falls, will test and demonstrate methods to produce high-quality antimony trisulfide from material sourced from Perpetua’s Stibnite Gold Project in central Idaho — a resource officials say could become the nation’s first major domestic source of the critical mineral.

 

Antimony is a key material used in defense systems, ammunition, batteries, solar glass and flame-retardant products. The United States currently relies heavily on foreign suppliers, with China and Russia dominating global production.

 

The launch marks a major step in a government-industry effort to rebuild a secure “ground-to-round” domestic antimony supply chain after China stopped supplying the United States with the specialized antimony trisulfide used in more than 300 types of ammunition in 2021.

 

The ribbon-cutting ceremony on July 29 brought together Idaho Governor Brad Little, Lieutenant Governor Scott Bedke, U.S. Representative Mike Simpson, Idaho National Laboratory Director John Wagner and Perpetua President and CEO Jon Cherry.

 

"From the mountains of central Idaho to the national laboratories advancing America's defense and energy capabilities, today's milestone shows what's possible when industry, government, and scientific innovation work together on practical domestic solutions," said Jon Cherry, President & CEO of Perpetua Resources. 

 

"As construction advances at the Stibnite Gold Project, this pilot plant extends that momentum downstream by helping establish the capabilities needed to produce military-grade antimony materials here in America. Together, these investments are laying the foundation for a secure, end-to-end domestic supply chain that strengthens national security while creating long-term economic opportunity."

 

The pilot plant combines Perpetua’s antimony resource with Idaho National Laboratory’s advanced materials expertise to develop processing capabilities, train workers and support future commercial-scale production of critical minerals.

 

"This pilot plant is more than a demonstration facility; it's an investment in the nation's critical mineral future," INL Laboratory Director John Wagner said. "The data and operational experience generated here will help advance domestic antimony production while demonstrating how national laboratories, industry and government can work together to strengthen America's supply chains and national security."

 

Defense officials said the project could help reduce vulnerabilities in the U.S. military supply chain.

 

"Establishing resilient domestic supply chains for critical minerals is vital to our national defense," said Col. Steve Adcock, Portfolio Management Executive Ammunition & Energetics at Picatinny Arsenal. 

 

"This pilot plant represents an important step toward reducing America's dependence on foreign sources of antimony while strengthening the industrial capabilities needed to support our warfighters. Partnerships like this help ensure the United States can reliably access the materials essential to military readiness."

 

The project builds on years of federal support aimed at restoring domestic critical mineral production. Perpetua’s Stibnite Gold Project contains the only identified domestic reserve of antimony and is being developed alongside significant gold production.

 

"We've worked to rebuild America's critical mineral supply chains because our national security depends on them," said U.S. Representative Mike Simpson (R-Idaho). 

 

"Today's ribbon cutting is a significant milestone in that effort. By bringing together Perpetua Resources, the Idaho National Laboratory, and the U.S. Army, this project demonstrates how Idaho is helping strengthen our nation's defense, expand domestic manufacturing capabilities, and reduce our reliance on foreign sources of critical minerals. I'm proud to have supported this partnership from the beginning and look forward to seeing the important role it will play for our country."

 

Idaho officials said the project strengthens the state’s role as a hub for critical minerals, innovation and advanced manufacturing.

 

"This partnership between Idaho National Laboratory and Perpetua Resources is a major step toward securing America's critical mineral supply chain and reducing our dependence on foreign-controlled resources," said Idaho Governor Brad Little. 

 

"By combining Idaho's abundant natural resources with world-class innovation, we are strengthening our national security, creating good-paying jobs, and reinforcing Idaho's leadership in the industries that will power America's future."

 

The Stibnite Gold Project sits in the historic Stibnite Mining District, which supplied antimony and tungsten during World War II to support U.S. military efforts. After more than a decade of scientific studies, engineering work, environmental review and stakeholder engagement, the project received final federal approvals in 2025 and has moved into early works construction.

 

Perpetua said infrastructure upgrades are underway to support full-scale development, with the project expected to help restore domestic antimony production while delivering environmental restoration, jobs and economic benefits.

 

The company said the pilot plant and Stibnite Gold Project together represent a broader effort to rebuild U.S. critical mineral independence, strengthen national security and reduce reliance on foreign-controlled supply chains.