The Khovu-Aksy Cobalt-Arsenide Deposit, Republic of Tuva, Russia: New Perspectives on the Problems of Production and Renewal of Processing

The Khovu-Aksy Ag–Bi–Cu–Ni–Co arsenide deposit discovered in 1947 was explored in detail by 1954. The Tuvakobalt Mining Complex mined veins cutting skarns in the Khovu-Aksy ore field and used hydrometallurgical process of ores to obtain bulk concentrate in accordance with the ammoniac–carbonate procedure in 1970–1991. During 20 years of operation, 12 000 tons of cobalt concentrate were produced; this concentrate was processed at the Ufaley plant to produce refined Co, Ni, Cu, and Ag. Huge adit dumps of barren material containing oxidized arsenides and sulfides were accumulated and more than 2 million cubic meters of hydrometallurgical wastes are dumped in six disposal pits on the industrial site. The retained cobalt reserves (more than 16 kt) and reserves in the disposal pits (more than 2.5 kt) are valuable critical minerals.