在黄铁矿、磁黄铁矿或砷黄铁矿等难浸硫化矿中,金往往以细浸染、亚微观颗粒出现。这种矿石中的金是可能通过磨矿解离出来;直接氰化时一般金的提取率仅为20～60％,而且氰化物的耗量很大。现时将硫化矿矿石及精矿进行预先氧化的方法中,最主要的是用高压釜、化学试剂、预先充气及焙烧。近年来细菌预氧化法已成为一种处理硫化矿的可供选择的方法。 In pyrite, pyrrhotite or arsenopyrite and other refractory sulphide ores, gold is often disseminated, submicroscopic particles appear. The gold in this ore is likely to be liberated by grinding; the direct gold cyanide extraction rate of only 20 to 60%, and cyanide consumption is large. At present, among the methods for pre-oxidation of sulfide ores and concentrates, autoclaves, chemical reagents, pre-aeration and roasting are the most important. Bacterial pre-oxidation has become an alternative method of treating sulphide ore in recent years.