Bismuthian Jamesonite (“Sakharovaite”) in Ores of the Sredny Golgotai Gold Deposit, Eastern Transbaikal Region, Russia

Resumo

The new data for the segregations, paragenetic assemblage, and composition of bismuthian jamesonite from gold–quartz mineralization at the Sredny Golgotai deposit located in the eastern part of the Mongolia–Okhotsk orogenic belt are reported. This mineral occurs as two varieties (I, II), which are slightly different in composition and chemically close to bismuthian jamesonite (“sakharovaite”) described from the Ustarasai deposit. In contrast to variety II, variety I is Cu- and Fe-free. The electron microprobe study has revealed that varieties I and II are close to jamesonite and tintinaite, respectively. The data obtained make it possible to conclude that individual sulfosalt species of the proper tintinaite and jamesonite series, which are close in composition, are probable members of the tintinaite–kobellite series. It is assumed that the Cu- and Fe-free variety of bismuthian jamesonite close in composition to “sakharovaite” is an individual mineral species.