Last week, the U.S. District Court for the District of Idaho denied a motion for a preliminary injunction to halt construction of the Stibnite Gold Project. Among other things, the project will establish a domestic source of the mineral antimony, which has an essential use in a range of defense applications, including munitions and military-grade antimony trisulfide, lead-acid batteries, advanced sensor and radar materials, and flame retardants. Historically, the United States has been dependent on foreign sources of antimony. China is the largest historical supplier and has restricted exports to the United States. This has left the National Defense Stockpile depleted.
“Antimony is among the minerals most vital to our national defense, and for too long the United States has relied on foreign adversaries to supply it,” said Principal Deputy Assistant Attorney General Adam Gustafson of the Justice Department’s Environment and Natural Resources Division (ENRD). “This decision allows construction to move forward on the most significant domestic source of antimony, and it reflects the Department’s commitment to defending projects critical to America’s national security.”
After years of environmental reviews, the U.S. Forest Service in January 2025 approved the Stibnite project, which is located in the Boise and Payette National Forests in central Idaho. A coalition of environmental groups challenged the approval and asked the court, before scheduled construction began, to halt work on the project’s access route and related facilities. The court denied that motion because plaintiffs had not made the required clear showing of imminent, irreparable harm. The ruling allows the authorized construction to proceed while the litigation continues.
Defense officials have identified the Stibnite project as the only domestic mine source capable of producing antimony in sufficient quantities to meet U.S. defense requirements in the near term. Over its life, the project is projected to produce roughly 115 million pounds of antimony, along with 4.2 million ounces of gold and 1.7 million ounces of silver. It will also reclaim a site disturbed by more than a century of historical mining, removing legacy mine tailings and restoring fish passage on the East Fork of the South Fork Salmon River.
Attorneys with ENRD’s Natural Resources Section and Wildlife and Marine Resources Section, together with the U.S. Attorney’s Office for the District of Idaho, are handling this matter.
