Abstract: A gold ore in Hunan Province contains high arsenic and carbon,and the gold concentrate obtained by flotation process is with low grade and recovery rate,which is a typical representative of refractory gold ore. The process mineralogy of gold ore was systematically studied by means of chemical multi-elements analysis,X-ray diffractometer,optical microscope, scanning electron microscope ( SEM),elemental chemical phase analysis and mineral liberation analysis ( MLA) in order to fully grasp the ore properties for optimizing the flotation indexes. The results showed that the average grade of valuable element gold in the ore was 3. 40 g / t,and the contents of harmful elements arsenic and carbon were 0. 36% and 1. 42%,respectively. The metallic minerals in the ore are mainly freibergite,scheelite,pyrite,arsenopyrite and siderite,while the non-metallic minerals are mainly quartz and sericite,followed by kaolinite,chlorite,serpentine and so on. The gold minerals in the ore are all natural gold with an average fineness of 999. 5‰. The morphology of the gold is mainly angular-grain and angulargrained,followed by long horned granular. The gold particle size of less than 19 μm accounted for 98. 95%,which belongs to the category of micro-fine particle. The distribution rates of monomer,exposed gold and sulfide wrapped gold in the ore are 5. 90% and 88. 79% under the condition of grinding fineness of -0. 074 mm accounting for 65%,respectively. And the total distribution rate of the two is 94. 69%,which is the maximum theoretical recovery rate of the gold at this grinding fineness. The recommended principle process flowsheet is gravity separation and flotation.

Key words: arsenic-containing gold ore,dissemination characteristic,particle size distribution,the occurence state of gold