Perpetua Antimony Loan Moves Stibnite Toward US Critical Minerals Production

Perpetua Resources

Perpetua antimony loan approval from the US Export-Import Bank gives Perpetua Resources a major financing route for its Stibnite Gold antimony-gold project in Idaho. The $2.9bn loan is intended to support full construction of one of the most strategically important US antimony projects.

Perpetua antimony loan support reflects Washington’s growing willingness to finance domestic critical minerals projects tied to defence, industrial security and supply-chain resilience. Antimony is used in military applications, flame retardants and lead alloys for batteries and cables.

Perpetua antimony loan funding is expected to become available in the second half of 2026, after standard requirements and documentation are completed. The company plans to cover full construction costs using the loan and its own funds.

The 13-year loan includes $2.4bn in upfront EXIM funding and a further $500mn to cover interest and fees during construction. Repayments are expected to begin in 2030.

EXIM Financing Strengthens Stibnite’s Construction Path

The EXIM approval is a major step for Perpetua because critical minerals projects often struggle to move from permitting to construction without large-scale financing. The Stibnite project now has a clearer path toward development.

The loan decision follows EXIM’s move to notify Congress of the proposed financing on 31 March. Perpetua had received a preliminary non-binding term sheet from EXIM in September 2025.

This timeline shows how strategic minerals financing is becoming more formalised. US agencies are not only identifying supply-chain gaps; they are using public financing tools to help build domestic capacity.

For Perpetua, the loan reduces one of the largest development risks. Construction funding can now be aligned with permitting, engineering, procurement and site preparation.

The project had already received its final federal permit in May 2025. That approval followed its selection for a federal expedited permitting initiative one month earlier.

Together, the permit and loan approval move Stibnite closer to becoming an operating domestic source of antimony, rather than only a strategic mineral proposal.

Antimony Reserves Carry Defense and Industrial Value

Perpetua estimates that the Stibnite Gold project contains 148.7mn lb of contained antimony reserves. That resource base gives the project clear strategic value for the US.

Antimony is a small-volume metal, but its applications are highly sensitive. Defence, batteries, cables and flame retardants all depend on reliable material availability.

The Stibnite project also includes gold, which can support project economics alongside antimony. This is important because many critical minerals projects need by-product value or multi-metal revenue to improve bankability.

The loan highlights a wider change in US minerals policy. Washington is increasingly treating domestic production, processing and financing as part of national security strategy.

For downstream buyers, the key question will be timing. The loan may be available in late 2026, but construction, commissioning and qualification will determine when material can actually enter the supply chain.

If developed successfully, Stibnite could reduce US exposure to external antimony supply risks and strengthen domestic access to a material used across defence and industrial applications.

The Metalnomist Commentary

Perpetua’s EXIM loan shows that the US is now willing to put serious capital behind critical minerals security. Antimony may be a niche market, but Stibnite proves that small-volume metals can carry large strategic value.