Two-stage gold mineralization of the Axi epithermal Au deposit, Western Tianshan, NW China: Evidence from Re–Os dating, S isotope, and trace elements of pyrite

The Axi gold deposit is one of the largest epithermal deposits in northwestern China and is characterized by multistage generations of pyrite associated with gold mineralization. Genetic models for superjacent epithermal Au and porphyry Cu systems involve either contemporaneous or episodic mineralization, implying different metal sources and ore-forming events. Nine pyrite separates from disseminated ores associated with pyrite-sericite-quartz...