FIRST FINDING OF NISBITE AND AUROSTIBITE IN THE EASTERN TRANSBAIKAL REGION

Abstract

Antimonides of Ni (nisbite NiSb2) and Au (aurostibite AuSb2) are genetically interesting rare minerals that appear at a very low activity of sulfide S and As. Since aurostibite is not subjected to cyanidation and amalgamation, the abundance of this mineral forces engineers to change the ore dressing technology. Nisbite was identified in a hydrothermal uranium deposit of the Red Lake Formation, Canada. The low activity of S in this area was related to the very high oxidative potential of alkaline-ultraacid (sodic) orebearing hydrothermal solutions. In Russia, nisbite was detected in the Festival’noe copper–tin deposit (Khabarovsk region) and the Zolotaya Gora gold deposit (the Urals). In the Zolotaya Gora gold deposit, nisbite occurs among native antimony in association with cuprostibite Cu2Sb, zlatogorite CuNiSb2, galena, ullmannite (Ni,Fe,Co)(Sb,As)S, seinajokite FeSb2, gudmundite FeSbS, and native lead.