湖南某钨矿床中银黝铜矿与黝锑银矿形成的物理化学条件分析

PHYSIOCHEMICAL CONDITIONS OF ARGENTIAN TETRAHEDRITE-FREDERICITE FORMATION FROM A TUNGSTEN DEPOSIT IN HUNAN PROVINCE

湖南瑶岗仙黑钨矿石英脉中伴生有银的矿化。银黝铜矿是形成最早和最主要的银矿物。部分银黝铜矿被后期的黄铜矿、方铅矿及铅硫盐矿物交代,分解出的银与残留在矿液中的银一起以黝锑银矿、深红银矿等银矿物的形式重新析出。根据银黝铜矿的产出特征和热力学计算,银黝铜矿在贫银,含银不饱和的弱酸-弱碱性中温条件下形成。黝锑银矿和其他银矿物则在晚期的贫铜富银低温热液中沉淀。

The sliver mineralization is associated with wolframite-quartz vein of Yaogangxian, Hunan province. Argentian tetrahedrite is the major silver mineral and formed in the earlist mineralization stage among silver minerals. Part of argentian tetrahedrite were replaced by chalcopyrite and galena. In later mineralization stages, the silver dissolved from argentian tetrahedrite and the silver kept in remainder hydrothemal brine led to the formation of some silver rich minerals such as frebrite, pyrargyrite, etc. According to characters of occurrence and themnodynamic calculation the argentian tetrahedrite was formed in mesothermal solution with poor silver and cooper under weak acid-basic condition.The freberite and other silver minerals were formed in later residual lowthermal and silver rich fluid.