Abstract: Based on the process mineralogy study of a certain refractory gold concentrate, leaching test was made on this ore by using sulfur-containing reagents such as thiourea, thiosulfate, thiocyanate and modified lime-sulfur synthetic solution (ML). The results show that this ore belongs to typical refractory ore with about 20% gold being enclosed by pyrite and arsenopyrite. ML can partially oxidize the enclosing minerals, resulting in an over 80% gold leaching rate, and therefore, is suitable for the leaching of this ore. The mechanism of the reaction between the leaching agent and the minerals is analyzed and postulated.

Key words: Sulfur-containing agent, Refractory gold concentrate, Leaching