摘要
金牙金矿床是一个典型的微细浸染型金矿床,金基本上都是以不可见(显微)金形式赋存在以毒砂为主的硫化物中。在单矿物含金量上毒砂超过黄铁矿20-30倍,在金的绝对金属量占有率上毒砂也高于黄铁矿5-7倍。研究结果还表明,在毒砂为主的硫化物中,不可见金的分布具有很大的不均匀性,这说明金很可能是以次显微金粒形式存在于硫化物中。同时,硫化物中金的分布还有一个明显的特点,即随着硫化物粒度减小,金的含量明显增加。这些发现为了解这类矿床中硫化物的含金性提供了新的资料。
The Jingyia gold deposit lies in the east part of th southwestern Guishou-western Guangxi gold belt.The host rocks of the gold deposit is Middle Triassic clastic rocks.The NW-trending fractures are the main passage ways for ore fluids and control the distribution of the orebodies.Based on microscopic observations,clectron-probe analysis,determination of the gold content in various minerals in the ore and gold carrier phase analysis,it is shown that there is no visible gold in the ore and that the gold occurs as microscopic invisible gold in sulfides(mainly arsenopyrite).The gold content(300—400 g/t)of arsenopyrite is 20—30 times that(10—15 g/t)of pyrite,and the gold occupancy(70—75%)of all arsenopyrite in the ore is 5—7 times that(10—15%)of all pyrite.This feature of gold distribution is rarely seen in various gold deposits all over the world.Electron-probe analysis shows that the distribution of the invisible gold in sulfides(especially arsenopyrite)is rather inhomogeneous;therefore,gold probably occurs as submicroscopic particles in sulfides.A detailed study alsp shows that the gold content of the sulfides,especially that of arsenopyrite,distinctly increases with a decrease of their grain size.
作者
钱定福
李玉衡
李志生
孙红惠
Qian Dingfu;Li Yiheng;Li Zhongsheng;Sheng Henghai(Zhengzhou Branch of the Institute of Multipurpose Utilization of Mineral Resources,MGMR)
出处
《地质论评》
1988年第4期361-368,共8页
Geological Review
