Geological characteristics and occurrence of silver in Xiabao Ag-Pb-Zn deposit,Lengshuikeng ore field,Jiangxi Province,East China

The Xiabao large-scale Ag-Pb-Zn deposit is located in the southwestern Lengshuikeng ore field,Jiangxi Province.The major mineralization can be divided into three stages:sphalerite-pyrite polymetallic stage(stageⅠ);galena-sphalerite-silver minerals polymetallic stage(stageⅡ);pyrite-quartz(calcite)stage(stageⅢ).The major ore minerals include sphalerite,galena,pyrite and silver minerals are studied in this paper on petrography and analyzed with Electron Probe Micro Analysis(EPMA).The EPMA also indicates that the most Ag presented in the ores occurs mainly as independent silver minerals,and rare Ag in sulfides.The dominant silver minerals are akanthite and native silver,which occur in the crevasse of ferromanganese-carbonate as crevasse silver or in the clearance of ferromanganese-carbonate and early sulfides as intergranular silver.In addition,there are also some micro canfieldites, Ag-bearing tetrahedrite,proustite,kustelite,aerosite,and eugenite,which occur in the clearance of ferromanganese-carbonate as submicroscopic structure or in galena,sphalerite or other sulfides as unmixing of solid solution structure.The fact that a large number of major silver minerals occur in ferromanganese-carbonate probably indicates a genetic relationship between silver mineralization and ferromanganese-carbonate.