Composition And Elemental Characteristics Of Chalcopyrite In Tongling,Anhui

Characterization and elemental analysis of minerals is an important aspect of the research on mineral genesis and enrichment regularity,and it is also the basis of mineral resource estimation,ore dressing and smelting performance analogy,and feasibility analysis of ore deposit development.In this investigation,Optical microscope,SEM/EDX(Scanning electron microscope and energy dispersive X-ray),XRD(X-ray diffraction),and XRF(X-ray fluorescence)will be applied on a sample of chalcopyrite obtained from Jinlang Zhongming Copper Polymetallic Mine in Tongling,Anhui,China,to obtain geological characteristics of chalcopyrite,e.g.texture,mineralogical composition,crystal structure,and elemental composition of chalcopyrite samples.Then,based on the geochronological results of the Zhongming copper polymetallic deposit carried out by other scholars,metallogenic background in research area,the relationship between Mesozoic Magmatic Activity and mineralization are discussed.Finally,the formation process of the Zhongming copper polymetallic deposit is determined.The research further enriches the metallogenic resources in the research area,and provides theoretical support for prospecting work.The results show that:(1)Macroscopic analysis of the samples reveal that they have a heterogeneous layered structure,their main component being pyrite,chalcopyrite and sphalerite together making up the veins and the boundary zone of carbonate minerals.The surface of the samples contains small fine grains of chalcopyrite,pyrite and fluorite impeded on the surface of the surrounding carbonate matrix that range from fine grained to grey green medium coarse grain texture cemented by calcite.(2)In the research,XRD was applied to obtain phase compositions and lattice parameters to analyze the crystal structure of the chalcopyrite samples,the intensity peaks of the XRD results were analyzed using Match3 software,the major metal minerals are mainly chalcopyrite,pyrite,sphalerite and siderite,there's also a small amount of galena,magnetite,etc.Gangue minerals are calcite,dolomite,quartz,fluorite,plagioclase,K-feldspar,diopside,chlorite,diorite,serpentine,etc.Chemical analysis determined by Energy dispersive XRD analysis and XRF revealed the average elemental compositions of Cu,Fe and S to be 19.35%,35.51%and 19.54 wt.%respectively.It also revealed high concentration of CO₃ due to high concentration of the carbonate minerals especially siderite that likely formed by combination of iron ions brought by the hydrothermal fluid with the host carbonate ions.(3)The experimental analysis showed the dominance of magnesian minerals in the rock matrix which due to metasomatic replacement of dolomite.It also indicates that the veins in the samples have a multi-stage characters and are made up of several mineral associations.The veins are mostly weathered and their nature is jointly related to the tectogenesis of the metamorphic rocks and the numerous of post magmatic and hydrothermal processes.This paper includes 20 pictures,5 tables,and 137 reference.