Critical Mineral Project Faces Hurdle After Trump Greenlight (1)

A recently approved mine that’s expected to be the nation’s first antimony project is set to face legal hurdles before it’s built, threatening the White House’s plan to bolster a domestic pipeline of critical minerals.

The Stibnite Gold project in central Idaho secured its last federal permits and is now moving to the construction-ready stage, the Trump administration announced Sept. 24. If the mine’s owner, Perpetua Resources, can raise the $2.2 billion it needs to build the mine, it would open up a 148 million pound lode of antimony—enough to supply about 35% of US demand in the first six years of operations, according to the company.

Antimony is a key mineral because it’s widely used for munitions in the defense sector. China is the world’s largest producer of the mineral, but it stopped exports in late 2024. President Donald Trump has moved to speed development of a domestic critical minerals supply chain to counter China’s dominance.

Two lawsuits, both before the US District Court for the District of Idaho, are already challenging the mine’s permits.

Either suit has the potential to stop the mine in its tracks, said John Robison, public lands and wildlife director at the Idaho Conservation League.

But in both lawsuits, the litigants have agreed not to file for a preliminary injunction, showing “we face far less hurdles,” said Marcelo Kim, Perpetua’s chairman.

Legal Challenges

In one case, filed in August, the Nez Perce Tribe argued the US Forest Service’s analysis of the mine’s environmental impacts were framed “in service of Perpetua Resources’ private goals and interests,” and the agency refused to analyze any less impactful alternatives to the plan, as required by the National Environmental Policy Act.

The mine, which is estimated to have a 38-year life span, will restrict “at least a generation of tribal members” from freely accessing the site for hunting, fishing, gathering, and travel, according to the complaint.

Further, construction and operations will create noise and visual impacts that will hinder tribal members’ spiritual practices, as well as crops, fish, and wildlife, the tribe said. Some of those impacts could be permanent, according to the Forest Service’s own analysis, the filing alleged.

The second case similarly alleges that, despite Perpetua’s claims that the project will improve environmental conditions at the site, the Forest Service found in its final environmental impact statement that the mine would degrade the environment, and that a “no action” alternative was the “environmentally preferred alternative.”

But the Forest Service approved the project anyway, despite adverse impacts on Chinook salmon, steelhead, bull trout, wolverines, and whitebark pine, each of which are protected as threatened species under the Endangered Species Act, according to the suit.

The Forest Service also violated the National Forest Management Act and Federal Land Policy and Management Act by allowing the construction of a new road and associated infrastructure through designated roadless areas and protected riparian conservation areas, the complaint alleges.

Both cases are being heard by Judge Amanda K. Brailsford.

Marty Boughton, Perpetua’s public affairs manager, said the Stibnite mine was “designed with environmental restoration intertwined into the mine plan.” During the mining process, the company will “comprehensively rehabilitate the abandoned Stibnite Mining District to not just a reclamation standard, but an even higher restoration standard,” she said.

Domestic Supplies

Will Tiedemann, regulatory conservation associate at the Idaho Conservation League—a litigant in one of the lawsuits—acknowledged it’s important for the US to have a reliable supply of antimony.

That’s consistent with the conclusions of the Trump-aligned Heritage Foundation, which recently said “the best option is to produce it domestically, and the next best option is to procure it from friendly governments. The worst option is to keep getting it from China.”

The price of antimony has shot up to record highs since China curbed its exports.

“But under capitalism, when that happens, other companies will start to say, ‘Do we have antimony at our mine? If so, let’s look at that,’” Tiedemann said.

Separately, the Trump administration could take an equity stake in the Stibnite mine, as it recently did in Lithium Americas Corp., a Canadian company that’s developing a lithium project in Nevada, Tiedemann said.

Were that to happen, a positive result for environmentalists is that there would be a responsible party—the federal government—that can’t go bankrupt and therefore could be relied on to pay for the cleanup, Tiedemann said.

On the other hand, “if the feds are involved, it puts more weight behind this mine going forward,” he said.

Aaron Mintzes, senior policy counsel at Earthworks, said both the Biden and Trump administrations have expressed interest in antimony, a gold byproduct.

In the meantime, Perpetua appears well positioned to raise the funds it needs to build the mine.

The company recently got a preliminary project letter and indicative term sheet from the Export-Import Bank of the US for a potential $2 billion in debt financing, according to Boughton. The bank’s board is expected to consider the proposal by the spring of 2026, she said.

Perpetua is in discussions to secure another $155 million of financial assurance needed to post its surety bond and expects to finalize the package soon, Boughton said. As soon as the financial assurance package is posted, “we will begin early works construction,” she said.

The cases are Nez Perce Tribe v. US Forest Service, D. Idaho, No. 3:25-cv-00498, filed 8/29/25 and Save the South Fork Salmon v. US Forest Service, D. Idaho, No. 1:25-cv-00086-AKB, filed 2/18/25.