Abstract:South Jiangxi is famous for its vein type tungsten deposits. These deposits contain predominantly wolframite, scheelite, cassiterite, chalcopyrite, pyrite, pyrrhotite, sphalerite, molybdenite and beryl as their metallic minerals, quartz, muscovite, orthoclase, topaz, tourmaline, calcite and fluorite as their nonmetallic minerals, and tungstite, molybdite, malachite, limonite, pyrolusite and kaolirute as their, secondary minerals. Of the major components, SiO2 is by far most abundant, and Al2O3, TiO2 WO3, S are also comparatively high. According to variations in major components, these vein type tungsten deposits might be grouped into three geochemical types: (1) Ti-rich deposits, characterized by high TiO2 (0.88%), low Al2O3 and relatively abundant SiO2 and WO3; (2) Al-rich deposits characterized by high Al2O3 (9.23%), extremely low TiO2 and SiO2 and relatively plentiful WO3. (3) Ti-, Al-poor deposits, characterized by low TiO2 (0.046% on the average) and Al2O3 (averaging 2.3%) as well as moderate amounts of SiO2. Correlation curves of WO3 versus SiO2 and S versus SiO2 indicate a close relationship between WO3 and SiO2: stable pay ore occurs where SiO2 is between 83% and 91%; poor ore exists where SiO2 is more than 91% or less than 83%; no mineralization could take place where SiO2 is less than 70% or more than 94%. As for S in the deposits, only a small number of samples have fairly high content, and the greatest amount of S is found where SiO2 is approximately 83%; S approaches nil where SiO2 is around 78% or 95%. These phenomena account for geochemically the existence of certain amounts of sulfides in the vein type tungsten deposits, the reduction of tungsten grade during the generation of quantities of sulfides, and the presence of sulfides-bearing tungsten-deficient quartz veins. Sn and polymetallic combinations (Cu, Pb, Zn, Bi) are among the most important minor elements in these deposits. Their high and variable contents and wide distribution have made them important indicators in the study of metallogeny. In WO3-Sn-Polymetallic elements triangular diagarm, vein typetungsten deposits fall into three areas, i. e., W-Sn area, W area and W-polymetallic elements area. On such a basis the vein type tungsten deposits in south Jiangxi might be spatially separated into three belts distributed semi-circularly around Dayu Mountain: W-Sn belt (Belt I),W belt (Belt II) and W-polymetallic elements belt (Belt III). From Belt I to Belt III, Sn decreases tremendously while polyrmetallic elements increase obviously, WO3 remains stable whereas WO3 in wolframite decreases accompanied by the gradual increase in impurities in this mineral. AIJ this shows unequivocally that there exist a regional zoning in metallogeny for the vein type tungsten deposits in south Jiangxi.
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王成发.1984.赣南脉状钨矿的地球化学特征[J].矿床地质,3(2):76~84.1984.Geochemistry Of Vein Type Tungsten De,Posits In South Jiangxi[J].Mineral Deposits3(2):76~84
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