Ore-forming mechanism of quartz-vein-type W-Sn deposits of the Xitian district in SE China: Implications from the trace element analysis of wolframite and investigation of fluid inclusions

The Xitian W–Sn district is located in eastern Hunan Province of SE China and comprises the Heshuxia, Goudalan, and Longshang W–Sn deposits. Our study on the occurrence, mineral assemblage, and geochemistry of the orebodies shows that quartz-vein orebodies are dominant mode of mineralization and can be divided into three stages: stage I, quartz–molybdenite–wolframite (I); stage II, quartz–wolframite (II)–polymetallic sulfides; and stage III,...