Typomorphism of Pyrite from the Ugakhan Gold Deposit (Baikal–Patom Highlands)

The results of studying the isotopic, geochemical, and TEDS properties of various generations of pyrite and pyrrhotite from the Ugakhan deposit, Bodaibo district of Irkutsk region, are presented. Differences in the composition of impurities are established. Early pyrites (py-I and py-II) are characterized by the presence of Ni, Co, Cr, and Au admixtures, the electronic type of conductivity, and values of δ 34 S ~ +5.6‰; py-III is characterized by a decreased amount of Ni, Co, and Cr, and an increased amount of As, the hole type of conductivity, and δ 34 S from +8.6 to +9.1‰. Post-ore py-IV and py-IV Q are characterized by the smallest admixture concentrations, the electronic type of conductivity, and isotopically lighter sulfur (δ 34 S ≤ +3.8‰).