西藏甲玛铜多金属矿金的赋存状态

摘要

通过野外地质勘探调查、光片鉴定和电子探针分析等手段对西藏甲玛铜多金属矿中伴生元素金的赋存状态进行初步研究.矿床中金以独立矿物为主,主要形成于热液成矿期中的绢云母-石英-方解石和方铅矿-闪锌矿-黄铁矿两个阶段.在绢云母-石英-方解石阶段,金主要以客晶方式莹网脉状、团块状分布于早期形成的黄铜矿、斑铜矿和闪锌矿等金属硫化物粒间孔隙中；在方铅矿-闪锌矿-黄铁矿阶段,金主要以自然金或含银自然金等独立矿物形式产出,亦呈自然金的形式分布于闪锌矿的粒间或包裹于其中.%Through a preliminary study of occurrence of gold by geological investigation, microscope identification, electron microprobe analysis, the authors provide a theoretical basis for comprehensively utilizing minerals. It is found that Au exists in the form of an independent mineral. Au mainly forms in the two mineralization periods, that is the sericite-quartz-calcite period and galena-sphalerite-pyrite period, which belong to the period of hydrothermal mineralization. In the period of the sericite-quartz-calcite metallogenic epoch, Au presents mainly in the way of chadacryst in the shape of net vein and block, and is distributed over the interstice of particles in metal sulfides such as chalcopyrite, bornite and sphalerite which formed in the early period. In the perid of the galena-sphalerite-pyrite metallogenic epoch, Au mostly appears in the form of independent minerals as native gold or silver-bearing native gold. It is distributed over or wrapped in the intergrains of sphalerite and also presents in the form of native gold.