Perpetua Resources received a letter of interest from the Export-Import Bank (EXIM) of the USA to progress its Stibnite Gold project.  

The letter of intent from EXIM comes under its “Make More in America” and “China and Transformational Export Program” initiatives for debt financing of up to US$1.8Bn. The Stibnite Gold project in Idaho, USA, was taken over by Perpetua Resources (previously Midas Gold) in 2009. In August 2023, the US Department of Defense (DoD) awarded an Ordnance Technology Initiative Agreement (OTIA) of up to US$15.5M to Perpetua Resources to demonstrate a US domestic antimony trisulphide supply chain using ore from its Stibnite gold project.  

Antimony trisulfide is used in key military applications, and the USA is reliant on imports of antimony metal as feedstock for further processing. Antimony’s main use is in flame retardants, while its other key application in lead alloys is largely met by recycled antimonial lead. A rapidly growing application is in solar PV, where antimony chemicals help improve the efficiency of capturing solar energy. 

Last month, The United States Antimony Corporation (USAC), which operates the last standing antimony refinery in the USA in Thompson Falls, suspended its Mexican mining and smelting operations, cutting off a key integrated supply chain for the USA. Mexico only accounted for a small percentage of the USA’s feedstock. A decade ago, China still accounted for over two-thirds of antimony metal to the USA, steadily decreasing to less than 30% since 2020. India, Vietnam (using Russian ores), Myanmar and Thailand have been the top suppliers to replace the reliance on China. 

Based on the 2021 feasibility study of Stibnite Gold, the mine will produce around 50kt contained antimony over 9 years (as a by-product of gold as the main economic mineral). According to the mine plan, peak production in year 2 could account for over 10% of global antimony mine production. Project Blue’s data shows that the mine will be important to return the antimony market to a healthy balance once commissioned, although this also includes ramp ups and steady supply at other key operations. However, it will be short-lived unless reserves can be extended, and based on the investment interest the limited feedstock will be supplied into military stocks.  

As a result, Stibnite Gold is not likely to be a structural solution to help curb elevated antimony prices, which have persisted since 2021 as a result of tightening concentrate supply. Project Blue forecasts antimony prices to remain elevated with little relief currently visible in the pipeline.