贵州某卡林型金矿的载金矿物特征及金赋存状态  

Characteristics of gold-bearing minerals and gold occurrence state of a Carlin-type gold ore deposit in Guizhou Province,China

作　　者：吴甜甜 沈智慧[1,2,3] 邱跃琴 赵宏龙[4] WU Tiantian;SHEN Zhihui;QIU Yueqin;ZHAO Honglong(College of Mining,Guizhou University,Guiyang 550025,China;National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas,Guiyang 550025,China;Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources,Guiyang 550025,China;Analysis and Test Center,Guizhou Institute of Technology,Guiyang 550003,China)

机构地区：[1]贵州大学矿业学院,贵州贵阳550025 [2]喀斯特地区优势矿产资源高效利用国家地方联合工程实验室,贵州贵阳550025 [3]贵州省非金属矿产资源综合利用重点实验室,贵州贵阳550025 [4]贵州理工学院分析测试中心,贵州贵阳550003

出　　处：《矿物学报》2024年第1期73-83,共11页Acta Mineralogica Sinica

基　　金：贵州省科技计划项目(编号:黔科合基础-ZK[2021]一般256)。

摘　　要：为合理制定提金工艺及高效回收金,采用光学显微镜下鉴定,结合化学分析、X射线衍射(XRD)、X射线光电子能谱(XPS)及电子探针X射线显微分析(EPMA)等手段,研究了贵州某卡林型金矿的载金矿物特征及金赋存状态。结果表明,矿石含金4.30 g/t,w(S)、w(As)分别为2.97%和0.35%。S、As主要以-1价态存在,说明矿石为原生金矿。矿石主要为粒状、草莓状、生物假象、交代和条带状结构,矿石中主要硫化物为含砷黄铁矿和毒砂,主要脉石矿物为石英、碳酸盐矿物和绢云母等。含砷黄铁矿多与石英和碳酸盐矿物连生,少数被隐晶质石英和炭泥质包裹,部分呈环带或弯曲状生物遗迹特征。94.88%的金以包裹金形式存在,含砷黄铁矿为主要载金矿物,其中金分布率为75.81%。不同形态的含砷黄铁矿中Au含量高低为:细粒状>生物碎屑状>草莓状>粗粒状,Au-S、Au-As之间均无正相关性。含砷黄铁矿中均赋存有晶格金和纳米金颗粒,金整体呈不均匀稀疏浸染状分布。研究结果可为贵州及其它地区卡林型金矿预处理-浸金工艺的制定提供理论指导,有效氧化或破坏载金含砷黄铁矿和石英包裹体及防止预处理过程中金的二次包裹有利于提高金回收率。In order to formulate reasonable gold extraction technology for recovering gold efficiently,the characteristics of gold-bearing minerals and gold occurrence state of a Carlin-type gold ore deposited in Guizhou Province,China,were investigated by using methods of optical microscopic identification,chemical analysis,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and electron probe X-ray microanalysis(EPMA).The results show that the ore has gold grade of 4.30 g/t,w(S)and w(As)contents of 2.97%and 0.35%,respectively.S and As occurred mainly in-1 valence state,indicating that the ore is a primary gold ore.Granular,framboid,biological shaped,metasomatic,and banded structures are main structures of the gold ore.Main sulfides of the ore include arsenic-bearing pyrite and arsenopyrite,while main gangue minerals of the ore include quartz,carbonate minerals,and sericite.The arsenic-bearing pyrites are mostly associated with quartz and carbonate minerals,and a few of them were included in cryptocrystalline quartz and carbonaceous argillaceous minerals.Some of them are characterized with ring-shaped or curved biological remains.94.88%of gold in the ore occurred in the form of inclusion gold.Arsenic-bearing pyrite is the main gold-bearing mineral,which contains 75.81%of gold in the ore.Au contents in different formed arsenic-bearing pyrites are decreased gradually from fine-granular one,bioclastic one,framboid one to coarse-grained one.In addition,there is no positive correlation between Au and S,Au and As.The gold occurred in forms of substituting ion in pyrite lattice and nano-particle inclusions in arsenic-containing pyrite grains,and it is generally disseminated unevenly and sparsely in the arsenic-containing pyrite.The research results can provide theoretical guidance for the formulation of pretreatment-gold leaching process for treating ores of the Carlin-type gold deposits in Guizhou or other regions.Furthermore,the effective oxidation or destruction of gold-bearing pyrite and quartz inclusions,and the pre

关 键 词：卡林型金矿 矿石结构 载金矿物 嵌布特征 赋存状态 

分 类 号：TD912[矿业工程—选矿]