The first parts of an antimony processing plant arrived at the Idaho National Laboratory (INL) in late May, marking a significant milestone in a collaboration with Perpetua Resources Corp (TSE: PPTA) (NASDAQ: PPTA). This delivery advances a partnership that Perpetua announced with the lab in December.
Under the agreement, the INL — via its primary contractor Battelle Energy Alliance — will host, commission and operate the processing plant. Once up and running, the facility will process material from Perpetua’s Stibnite gold-antimony operation to demonstrate production of high-quality, military-spec antimony trisulfide for the United States Army.
“Once assembled, this pilot will showcase a new pathway to strengthening a secure, domestic supply chain for critical minerals,” the INL said on social media last week, “an important step forward for U.S. national security.”
This laboratory serves as the U.S. Department of Energy’s lead site for nuclear energy research. It also conducts work on strategic national security tech and critical materials like antimony.
“From satellites and surveillance systems to precision-guided munitions and fighter jet engines, critical materials are at the foundation of America’s military strength,” the lab’s Communications Specialist, Brandon Hallmark, stated recently.
The pilot plant will leverage INL’s expertise in mineral characterization, geochemical modelling and material separation. This aligns with the lab’s expanded emphasis on critical materials research to support energy security and defence needs.
Read more: NevGold Corp. reports antimony grades up to 53.7 per cent at Nevada project
Perpetua advances Stibnite construction and secures major financing
The development comes as Perpetua continues early works and critical-path construction at its Stibnite gold-antimony project in central Idaho. Activities include upgrades to the Burntlog Route for safer access, worker housing, powerline improvements and more drilling.
It also follows Perpetua securing approval for a US$2.9 billion loan from the U.S. Export-Import Bank. This financing will support full construction toward planned 2029 production of antimony and gold.
The construction ramp up and latest major financing helps address U.S. efforts to establish a domestic supply chain for antimony. This mineral is currently subject to heavy reliance on foreign sources, primarily China.
U.S. antimony potential remains limited but demand persists
Stibnite stands as one of only a few U.S. sites with meaningful antimony production potential in the near term. Domestic supply remains constrained despite heightened strategic interest.
Antimony prices declined from their mid-2025 peak, driven by earlier supply disruptions and export controls, but demand stays robust. Key drivers include defence needs for munitions, flame retardants, semiconductors, solar panel components and battery technologies. Substitution options exist for some uses, yet overall requirements for critical applications continue to support the market.
Other companies are pursuing similar opportunities. Sunshine Silver is also constructing an antimony refinery in Idaho alongside its plans to reopen the state’s historic Sunshine Mine, targeting significant U.S. supply. In Q3 of 2025, Nova Minerals Ltd (OTCMKTS: NVAAF) (FRA: QM3) (ASX: NVA) received a US$43.4 million U.S. government award to accelerate antimony work at its Estelle project in Alaska.
Moreover, NevGold Corp (CVE: NAU) (OTCMKTS: NAUFF) (FRA: 5E50) is advancing its Limousine Butte project in Nevada where it just reported high antimony grades of up to 53.7 per cent in stockpiles. The junior aims to complete an inaugural mineral resource estimate quickly while targeting near-term production from existing materials.
These developments reflect broader U.S. initiatives to reduce dependence on imported critical minerals through domestic projects and processing innovation.
Read more: NevGold launches 20,000-metre drill campaign at Nevada antimony-gold project
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