Hydrothermal fluid evolution of the Sn-W mineralization in the Parrilla ore deposit (Caceres, Spain)

This orebody is a stockwork of quartz veins with scheelite and cassiterite. The ore fills fractures in the greywacke schist complex which has been intruded by Hercynian granites, the Sn-W minerals being accompanied by arsenopyrite, sphalerite, chalcopyrite, pyrite, Bi sulphosalts, pyrrhotite, muscovite and tourmaline. The fluid inclusions in quartz and scheelite indicate three stages of fluid circulation. The first stage is characterized by aqueous and complex CO (sub 2) -aqueous inclusions (<7 wt.% NaCl equiv.) trapped at 350-225 degrees C. The second stage is represented by low-salinity aqueous inclusions (<7 wt.% NaCl equiv.) trapped at homogenization T of 225-150 degrees C, and the third stage has mixed salt-aqueous inclusions (<31 wt.% NaCl equiv.) trapped at homogenization T of 150-70 degrees C.