Nasdaq- and TSX-listed Perpetua Resources has locked in $400-million in equity commitments through a bought deal financing and private placement, advancing a funding plan for its flagship Stibnite gold and antimony project in Idaho, US.

The Boise-based company said on Wednesday that it entered into an agreement with a syndicate of underwriters led by National Bank of Canada Financial Markets and BMO Capital Markets to sell 22.7-million shares at $13.20 apiece, raising $300-million. It also announced a concurrent $100-million private placement with hedge fund Paulson & Co.

The financing, expected to close on Monday, forms part of a comprehensive capital strategy that includes a previously disclosed application for up to $2-billion in debt from the Export-Import Bank of the United States (Exim). The company would designate the proceeds of the offering and the private placement toward equity requirements for the Exim financing.

If the Exim application and planned royalty financing were successful, Perpetua said it would have enough capital to fully fund the $2.2-billion construction of the Stibnite project. The company also aims to cover cost overruns, debt service, working capital, and further exploration.

Perpetua is seeking additional backing for environmental obligations tied to the project. The company said it was in “advanced discussions with potential partners” to secure a $155-million guarantee covering reclamation bond requirements. In return, Perpetua would offer either a gold stream or a net smelter return royalty of up to 3.9%.

“The proposed royalty and financial assurance arrangement is expected to be formalised in summer 2025,” the company said. The goal is to unlock final permits and trigger construction later this year.

The company also granted underwriters an option to purchase an additional 3.4-million shares, potentially increasing total proceeds from the bought deal to $345-million.

The capital raise comes amid growing momentum for the Stibnite project, which is being positioned as both a critical domestic gold source and the only US mined supply of antimony, which is a key material in military munitions. The US Department of Defense awarded the project $59.2-million under the Defense Production Act to support permitting and preconstruction work.