United States Antimony Corporation announced that the Department of Defense and the Defense Logistics Agency have approved the third and final sample of antimony trisulfide supplied by the company. The samples were all taken from material obtained via concentrating feed from ore at the Sierra Guadalupe mines in the state of Zacatecas Mexico. The Company, in Third Quarter of 2022, entered into a purchase agreement for the ownership of the mining concessions at the Sierra Guadalupe Mines and is currently engaged in negotiations for the surface rights.

The mines were worked prior to 1970 and the approved material came from concentrate made from dump rock generated from that mining effort. The Guadalupe supplied a small amount of high-grade feed for direct smelting in 2016-2018 that had an average grade of approximately 32% antimony.