“Invisible” Gold and Other Impurity Elements in Pyrite and Arsenopyrite from the Mayskoe Deposit (Chukotka)

The gold-bearing sulphides (pyrite and arsenopyrite) from disseminated refractory ores of the Mayskoe gold deposit (Central Chukotka) were studied using modern precision methods (electron microprobe analysis and laser ablation-inductively coupled plasma-mass spectrometry). The distribution patterns of macro elements (As, Fe, S), as well as trace elements (Ni, Zn, Sb, Co, Cu, Ag), in pyrite and arsenopyrite, including the content of “invisible” Au and its correlation with other elements were studied. Based on recieved data, the sequence of crystallization and the relationships of gold-bearing sulphides at the main and most productive gold–sulphide stage of the deposite formation were established.