Felix Gold (ASX:FXG) has announced updates on the metallurgical testwork and processing developments, following approvals to extract bulk ore samples from the Treasure Creek Antimony Project in Alaska.
Excavation, hand sorting, and bagging of massive stibnite vein has been successfully completed on site, delivering a 370kg ‘high-grade’ sample to Core Resources for characterisation and testwork.
Core Resources has reported that the ore samples exceed US Military Concentrate Specification (MIL-A-22131). This confirms the ‘exceptional’ direct-shipping quality of the ore prior to processing.
Direct smelting trials also conducted by Core Resources have resulted in untreated ore successfully converted directly to antimony metal, proving a direct pyrometallurgical pathway without the need for any prior processing.
With regards to the leach testwork and electrolyte production, Felix reports that the alkaline sulfide leach testwork generated purified electrolyte for downstream electrowinning.
The work achieved up to 98% antimony extraction at 75℃ and more than 90% recovered within the first two hours, indicating strong recoveries and rapid leach kinetics.
Electrowinning Trials conducted by the University of British Columbia produced high-purity antimony from Blue Coast-generated electrolyte feed, confirming an ore-to-metal pathway. Final assays remain pending on this.
Felix, together with Core Resources, achieved around 99% antimony extraction at 150-300 micron feed size, which the companies say supports simplified hydrometallurgical processing conditions.
Finally, Worley has completed its site selection assessment on behalf of Felix, supporting the evaluation of toll treatment and dedicated processing facility for the company.
Executive Director Joseph Webb says that the ore characteristics are important to note.
“This is not concentrate – this is ore: Direct Shipping Ore that meets military-grade specifications,” Webb says.
“There are no known sources to the company’s knowledge of military-grade antimony concentrate in the Western world – and this exceeds that threshold straight out of the ground.
“It can then be converted to metal – either by direct smelting of untreated ore or by leach and electrowinning – both without pre-treatment and at coarse grind.
“The quality of the ore drives a cascading effect across the entire development profile – selective mining of high-grade material enables a small physical footprint and minimal waste, while the purity of the feed simplifies processing and removes multiple conventional steps.
“All of this sits within a US policy environment actively seeking a domestic supply of critical minerals, supported by established infrastructure and a brownfields setting at Treasure Creek. In a market where the United States has no integrated domestic antimony supply chain, that combination is highly significant.”
Felix Gold is an exploration company focused on the Treasure Creek antimony and gold project in Alaska.
Write to Amy Rotman at Mining.com.au
Images: Felix Gold
