The U.S. Department of Defense (DOD) Defense Logistics Agency (DLA) awarded Perpetua Resources Corp. two funding grants to study the domestic production of military-grade antimony trisulphide, an essential component in ammunition and dozens of other defense materials. Perpetua will receive $200,000 in total to evaluate whether antimony from the Stibnite Gold Project can meet military specifications (Mil-Spec) to help secure America’s defense and commercial ammunition supply chain while also evaluating alternate methods for purifying antimony trisulfide.

“Antimony from the Stibnite gold project site served our national defense needs during World War II and Perpetua is confident we can be part of the solution again,” said Laurel Sayer, president and CEO of Perpetua Resources. “We are grateful for this opportunity to work with the DOD to demonstrate that our project can develop reliable and domestically sourced antimony trisulfide for defense and commercial ammunition. It would be a great honor to support the independence of our country’s defense supply chains and the brave men and women who serve our country.”

Perpetua submitted two proposals to DLA’s “Production of Energetic Materials and Associated Precursors” Small Business Innovation Research (SBIR) grant solicitation. As described in the grant’s objective, the program is focused on reducing “foreign reliance and single points of failure for the domestic manufacturing of energetic materials” through the development of a domestic source. After a competitive review process, Perpetua was awarded SBIR Phase 1 funding of $100,000 for both programs. Each study is expected to be completed within the next six to 12 months.

The first program will test existing samples of antimony trisulphide ore from the project for development into antimony trisulphide to Mil-Spec. The second program will study alternative processing opportunities to develop Mil-Spec antimony trisulphide from high purity antimony metal. After the completion of the proposed programs, Phase 2 funding could be made available for more advanced stage pilot-scale testing within the next year. Together, the Phase 1 and Phase 2 programs could confirm the Project’s ability to provide the domestic antimony source needed to meet the defense procurement demand and support commercial markets.

Antimony trisulphide is produced from high purity antimony ore feedstock and is used in small and medium caliber munitions, mortars, artillery, mines, flares, grenades, shoulder-launched munitions and missiles. Currently, China, Russia, and Tajikistan control approximately 90% of the world’s antimony supply and the United States has no domestically mined source of the critical mineral. Perpetua’s proposed Stibnite Gold Project hosts one of the largest antimony deposits in the world independent of China, Russia and their interests.

Recent global conflict and supply chain instability has impacted access to the high purity antimony ore feedstock required to produce Mil-Spec antimony trisulphide. In June 2022, the House Armed Services Committee reported that Chinese and Russian geopolitical dynamics could “accelerate supply chain disruptions, particularly for antimony” and directed the Manager of the National Defense Stockpile to brief the committee on the five-year outlook for the antimony stockpile and supply chain.

The Stibnite gold project, located in central Idaho, is advancing through the sixth year of review under the National Environmental Policy Act. The Project is designed to restore environmental conditions in the historical Stibnite mining district while responsibly developing one of the highest-grade open pit gold resources in the United States and becoming the only domestically mined source of the critical mineral antimony. Mining activity first started in the district in the early 20th century for gold and silver. During WWII and the Korean War, the U.S. Government commissioned antimony and tungsten production from Stibnite under the authority of the Strategic Metals Act of 1939. The site produced over 90% of the antimony used by the U.S. during WWII and was influential in establishing Mil-Spec for antimony trisulphide.