Abstract: The main valuable elements of a foreign gold deposit are gold and copper，and the contents of silver meets the comprehensive utilization standard. The contents of serpentine and chlorite in gangue minerals are high， which leads to the low gold grade of on-site flotation concentrate. The gold contents of tailings is between 1.8 and 2.0 g/t. In order to optimize the existing flotation process and reagents system， flotation and leaching process was adopted to study the gold ore purification based on the properties of the ore. The results showed that: ①In the condition of grinding fineness of -0.074 mm accounting for 90%， the dosage of sodium hexametaphosphate of 2 500 g/t， the dosage of collector 1801 and amyl xanthate of （40+70） g/t， the dosage of terpenic oil of 10 g/t， the gold concentrate of gold grade of 158.6 g/t， gold recovery rate of 73.40% was obtained after two roughing， three scavenging and one cleaning. The copper grade and recovery rate are 8.79% and 73.75%， respectively， and the silver grade and recovery rate are 321.8 g/t and 74.22%， respectively. ② The Shengdi was used as gold extraction agent with the flotation closed circuit tailings. The gold leaching rate was 80.00% when the dosage of pH adjusting agent lime of 2 000 g/t， the dosage of gold extraction agent of 3 000 g/t， and the leaching time of 24 h. Finally， the comprehensive recovery rate of gold is 94.68%. The research results provide reference for the effective recovery of this type of the gold resources.

Key words: micro-fine particle gold, sliming, flotation, gold extraction agent with environmental protection