Occurrence and mineral chemistry of bismuth sulfide-telluride-selenide solid solutions (ingodite, joseite, and unnamed phase) in the Nakdong deposit, South Korea
Shin, Dong-Bok; Lee, Chan-Hee; Lee, Kwang-Sik
published: Jun 9, 2005
ArtNo. ESP154018103008, Price: 29.00 €
Bismuth sulfide telluride selenide solid solutions, such as ingodite (Bi(S, Te)), joséiteA (Bi4TeS2), selenian joséiteB (Bi4(Te,Se,S)3), and an unnamed phase (Bi2(Te,Se)) were formed during the AsBi mineralization in the Nakdong deposits, South Korea. Ingodite, a rarely reported mineral, has the general composition, Bi1.94Sb0.01Ag0.04Te1.03Se0.03S1.08, which is regarded as Te-rich ingodite. Compiled data of previous work indicates that joséiteA from the Nakdong deposits extends its compositional range toward joséiteB and there still remains an obvious compositional gap in the range of 19.7 to 24.6 at % S + Se and 16.4 to 21.9 at % Te between the two phases. Selenian joséiteB has an intermediate compositional range between Bi4Te2S and Bi4Te2Se through the exchange between S and Se. The unnamed phase, Bi1.97Sb0.02Te0.83Se0.12S0.01, with constant Bi/(Te + Se + S) ratio close to 2 but a variable Te/(Se + S) ratio from 5.7 to 8.2, is placed in the compositionally intermediate range between the two unnamed phases of Bi2Te and Bi2 (Te, Se) of Gu et al. (2001). Coexistence of native bismuth with joséiteB and the unnamed phase constrains their formation temperature below 266 °C.