Felix Gold Limited has successfully built, operated and demonstrated an end-to-end pilot plant design flowsheet for its proposed U.S. refinery, producing antimony metal ingots from ore sourced at the Treasure Creek project in Alaska.

The testwork program confirms a direct-smelt process route that bypasses conventional grinding, flotation and concentration stages. Ore was charged directly to the furnace from hand-sorting and coarse crushing, representing a materially shorter flowsheet.

The program was designed and supervised by MetaMets and conducted at an independent third-party metallurgical facility. Ore from the Bundtzen Vein was melted in an externally gas-fired silicon carbide crucible furnace before fume capture in a cartridge bag filter yielded antimony trioxide. Subsequent reduction trials with coal produced cast antimony ingots. Final refining remains planned for subsequent work.

“We did not model this pathway. We designed it, built it, ran it and made metal. Ore went in one end of the plant and antimony ingot came out the other end, through the same sequence of unit operations Frontier intends to build and operate at scale. That removes the single largest technical unknown standing between us and a U.S. refinery.”

— Joseph Webb, Executive Director

Felix Gold established Frontier Antimony Refinery Corp. as a 100%-owned Delaware subsidiary structured to serve as a dedicated platform for U.S. antimony refining and metal production. The U.S. subsidiary holds ore feed secured from Treasure Creek, a completed Worley/SLR U.S. site-selection and permitting study, and substantially advanced preliminary engineering.

This corporate structure aligns with the company's recent selection by the U.S. Department of Energy for negotiation of a financial award of up to US$18 million to advance the Treasure Creek Antimony Pilot Processing Facility under the Infrastructure Investment and Jobs Act Mines & Metals Capacity Expansion program. The proposed company cost share of 26.8% is to be provided in-kind through the delivery of ore.

Nearby in the district, United States Antimony Corporation reported transitioning to internal ore supply to fulfill defense contracts alongside capital expenditure of $2.8 million at its Ester Dome project.

Laboratory assays and the final refining stage are currently outstanding. Felix Gold expects to receive and report independent laboratory assays for head, fume and metal samples, while the balance of the crushed sample is planned to follow the same process route to cast a single larger ingot.

Read the full announcement: Pilot Plant Produces Antimony Metal