Структура распада твердого раствора Au-Ag в самородном золоте эпитермального месторождения Агатовское (Северо-Восток России)

The issue is considered on the example of the near-surface volcanogenic Agatovskoye deposit, located in the Tenkinsky District of Magadan Oblast. The morphology of native Au particles, their intergrowth with other minerals, assaying variations, and internal structure are described, as well as the spotted heterogeneity not typical for low-assay gold and caused by thermometamorphism associated with post-magmatic intrusions and subvolcanoes in the deposit area. The features of the Au-Ag solid solution decomposition structures in deposits of different depths are discussed. It is shown that the method of the Au-Ag solid solution decomposition depends on the cooling rate of the ore-forming system and can be used as a typomorphic feature, both in prospecting and for genetic constructions. The impulse for the Au-Ag solid solution decomposition in native gold is its thermal metamorphism and the subsequent cooling rate of the ore-forming fluid.