Abstract: Process mineralogy study was done on a low grade and fine-sized quartz vein type gold ore of fracture zone by adopting MLA mineral automatic detection technology and combined traditional chemical analysis, microscopic analysis and other methods. The results indicate, main valuable minerals in this ore were silver-bearing natural gold, carrier minerals of gold are arsenopyrite, pyrite, quartz,etc. Dissociable natural gold, gold still contained in pyrite and arsenopyrite, gold contained in gangue account for 61.24%、34.78% and 3.98% respectively when ore ground to -0.045 mm, theoretical recovery rate of gold is 96% around. The relationship between gold and arsenic mineral arsenopyrite in ore is close which would has a certain effect to cyanide gold refining.

Key words: Natural gold, Pyrite, Arsenopyrite, Occurrence state, Process mineralogy