Dispersed mineralization in granitic rocks in the Dukat ore field, the Russian Northeast: Sources and relationship with epithermal gold-silver and silver-base-metal ores

The dispersed mineralization in the Late Cretaceous leucogranite of the Dukat ore field comprises melanocratic high-sulfide epidote-feldspar, pyroxene-feldspar and low-sulfide allanite-fluorite-feldspar inclusions in greisenized intrusions. The silver-base-metal mineralization is composed of pyrite, pyrrhotite, small particles of Pb, Zn, Sn, Ag, and Sb sulfides and oxides, their native species, and intermetallic compounds; the rare-metal mineralization consists of REE, Th, U, Ti, Zr, Nb, Ta, and W oxides, silicates, and aluminosilicates. The isotopic Nd, Sr, and Pb isotopic compositions and geochemical characteristics of the mineralized inclusions, rock-forming minerals of granitoids, hydrothermal minerals of preore metasomatic propylites and orebodies at the Dukat deposit show that their components have been taken from heterogeneous domains of the Paleozoic juvenile continental crust of the Siberian Platform.