关键词: 金矿石, 阶段磨矿, 跳汰, 浮选

Abstract: The grade of a gold ore from Iran was 7.05 g/t.The gold minerals mainly existed in pyrite in the form of exposed and semi-exposed gold.The particle size of natural gold ranged widely，with 81.15% of fine grain gold particles (0.01~0.06 mm) and 18.85% of micro-fine gold particles.In order to determine beneficiation process of the ore，the mineral processing experiments were carried out.The test results showed that：①the process of stage grinding-stage separation can effectively reduce the loss of coarse gold particles in flotation process and avoid over-grinding in grinding process，meanwhile it was beneficial to the dissociation of unevenly fine gold-bearing minerals.②part of qualified gold concentrate can be recovered by using jigging machine from grinding products with fineness of -200 mesh accounted for 65%，which fully embodied the concepts of recover early and step separation.③the gold gravity concentrate with grade of 81.43 g/t and a recovery of 45.52%，the gold flotation concentrate with grade of 56.12 g/t and a recovery of 44.99% were obtained separately，and the comprehensive gold concentrate with grade of 66.52 g/t and a recovery of 90.51% was achieved by the process of stage grinding-jigging gravity-stage flotation.④cyanide leaching process was adopted to treat the tailings containing 0.74 g/t of gold，hence the leaching rate could reach 62.16% while the gold grade of final leaching residue was only 0.28 g/t.

Key words: Gold ore, Stage grinding, Jigging, Flotation