Study On The Processing Mineralogy Of Garnet In Hecuokeng Molybdenum Deposit, Fujian

The Hecuokeng molybdenum deposit is a typical skarn-type ore deposit, located in the Northwest Fujiant. Starting from field survey and sampling, the author carried out chemical analysis, microscope observation and scanning electron microscopy with energy dispersive X-ray analysis and X-ray diffraction to determine the chemical and mineralogical compositions, texture and structure of the ores with the emphasis on the processing mineralogy of garnet.The major minerals of the ores include andradite(～50%) and hedenbergite (～25%), with small amount of quartz, plagioclase, fluorite, molybdenite and scheelite in Hecuokeng molybdenum deposit. Andradite and hedenbergite make up to75%of the ores and occur as euhedral to anhedral granular agglomerate in schistose to flaky and graphic texture, with disseminated and banded structure. The results of scanning electron microscopy show that andradite contains SiO2(36.83%), Fe2O3(27.33%), CaO (32.28%) and A12O3(3.59%), while hedenbergite contains SiO2(50.01%), Fe2O3(14.63%), CaO (26.34%), MgO (3.64%), with impurities of MnO and A12O3(5.38%). Andradite is in close association with hedenbergite. The monomineral liberation degree of andradite is about85%under the condition of grinding fineness of82%below200meshes. The garnet with high Fe and low Al in Hecuokeng deposit is, to some extent, inferior to that of industrial standard in physical and chemical properties.The grade of WO3is0.02-0.07%and the content of Mo in scheelite can be high up to16%, making it difficult to obtain high quality of tungsten concentrates. Fluorite in ore was about5%with the grain size of0.05-0.5mm, with the possibility for recycling fluorite from quartz and plagioclase.