Geochemical Features of Sulfides of the Aktash Magnetite–Polymetallic Deposit, Western Karamazar, Tajikistan (LA-ICP-MS Data)

The distribution of trace elements in sulfides from various ores of the Aktash magnetite–polymetallic deposit (Tajikistan) is studied using the LA-ICP-MS method. Sulfides partly replace banded magnetite ores. Each sulfide type exhibits specific geochemical features. Galena from sulfide–magnetite ores contains a higher amount of elements of “high-temperature” association (Bi, Ag, Cu) than galena from pyroxene–sphalerite ores, which, in addition to Ag and Bi, also contains higher amount of elements of “medium-temperature” association (Se, Te, and Sb). Sphalerite from sulfide–magnetite and chlorite–pyrrhotite ores contains a higher amount of Fe, Cd, and Mn than sphalerite from pyroxene–sphalerite ores, which is characterized by elevated Co and As contents. Pyrite is depleted in trace elements except for As, the content of which is maximum compared to other sulfides. The Ag, Se, Bi, Zn, Cd, and Ni contents of chalcopyrite from chlorite–pyrrhotite ores are higher than in chalcopyrite from sulfide–magnetite and pyroxene–sphalerite ores. Chalcopyrite from pyroxene–sphalerite ores is characterized by elevated Pb, As, Ge, Te, and Sb contents. Relatively high Co, Ni, and Se contents are determined in pyrrhotite. In addition to Fe, Cu, Zn, Pb, and Au, which form minerals in all types of ores, we suggest that there is by-product extraction of the following elements from complex sulfide–magnetite, chlorite–pyrrhotite, and pyroxene–sphalerite ores (the Bi, Ag, Se, and Te contents of galena and Cd content of sphalerite are shown in brackets): Bi (19 520–24 650 ppm), Ag (7907–9650 ppm), Se (397–606 ppm), and Te (276–436 ppm) from galena concentrate and Cd (8525–27 670 ppm) from sphalerite concentrate.