广南老寨湾金矿金的赋存状态研究

GOLD-BEARING PROPERTY OF ORE ROCKS AND OCCURRENCE OF GOLD AT LAOZHAIWAN GOLD DEPOSIT OF GUANGNAN

野外取代表性矿样10t,经缩分破碎处理利用化学分析、透反两用偏光显微镜、X射线衍射、MLA、电子探针等测试手段对广南老寨湾金矿的工艺矿物学特征进行系统研究。结果表明,矿石岩石类型主要以沉积岩为主,矿石中金(Au)含量为1.62×10^(-6),电子探针点测数据显示,黄铁矿中金的含量在0.000~0.105%之间,黄铁矿确定为金(Au)的主要载体矿物;毒砂中金的含量在0.000~0.052%之间,毒砂很可能是金的载体矿物之一,除黄铁矿及毒砂之外,未发现其他载金矿物。经MLA分析,黄铁矿及毒砂中的金(Au)以超显微包裹体的形式存在,黄铁矿及毒砂嵌布粒度较细。最后笔者建议采用"黄药浮选-焙烧-浸出"工艺对该矿石中的金进行分选。

Methods of chemical analysis,refection polarizing microscope （PMR-POL） ,X-ray diffraction （ XRD）,mineral liberation analyser （MLA） and electron microprobe analysis （EMPA） are used to study the technological mineralogy and sorting properties of gold ore at Laozhaiwan gold deposit of with crushed 10 t samples from the field. It shows that the type of ore is mainly dominated by sedimentary rocks with grade of gold of 1.62×10^-6 ton. The content of gold in pyrite is between 0. 000~0. 105 % and pyrite is the main gold-carrying minerals. The content of gold in arsenopyrite is between 0. 000~0. 052 %, and arsenopyrite is probably one of the gold-carrying minerals. MLA analysis indicates that the gold occurs as ultra micro inclusions in pyrite and arsenopyrite and appears as extremely fine dissemination size. Therefore,it is suggested that the ＂xanthate flotation-roasting-leaching＂ process is used for the separation of gold in ores.