新疆东天山康古尔金矿金属矿物特征及其找矿意义

Characteristics of Metallic Minerals in the Kangguer Gold Deposit of Eastern Tianshan,Xinjiang,and Its Implications for Ore Prospecting

为了解金属矿物特征及其含矿性,通过光学显微镜观察、电子探针分析,对康古尔金矿的矿石和次火山岩金属矿物形态、粒度、化学成分等矿物标型特征进行了系统研究。结果表明,主要载金矿物为黄铁矿和磁铁矿,黄铁矿的含金性与As含量成正比,不同形态黄铁矿含金性从高到低依次是八面体、聚形或不规则、五角十二面体、立方体,Co/Ni值平均为18.24;磁铁矿的含金性最高,常与绿泥石共生;方铅矿富Ag、Se;闪锌矿富Cd贫Fe,闪锌矿Zn/Cd值平均为239.11;黄铜矿富Co,常呈团块状分布于矿床下部。结合次火山岩中金属矿物特征,认为绿泥石-磁铁矿化和次火山岩为重要的找矿标志。

On the basis of field work,systematic analyses were carried to characterize mineral typomorphic characteristics of ore and subvolcanic rocks,e. g. mineral forms,granularity,chemical constituents,using optical microscope observation and electron probe analysis to reveal the characteristics and the ore-bearing potentiality of metallic minerals. The results showed that the main gold-carrying minerals are pyrite and magnetite. The gold-containing quality in pyrite is in proportion to the content of As; the sequence of pyrite crystal forms is octahedron,combination or irregular form,pyritohedron and cube according to the gold-containing quality of different crystal forms with an average Co/Ni ratio of 18. 24. The gold-containing quality of magnetite is high and magnetite usually coexists with chlorite. The contents of Ag and Se in galena are relatively high,so the content of Cd in sphalerite and the content of Co in chalcopyrite. In addition,the content of Fe in sphalerite is relatively low and the average ratio of Zn/Cd is 239. 11. Chalcopyrite generally occurs in the lower part of the deposit in the form of crumbs. On the basis of characteristics of metal minerals in subvolcanic rocks,chloritization-magnetite and subvolcanic rocks are considered as the significant indicators for ore prospecting.