紫金山铜金矿中金铜银的赋存状态研究

采用矿物自动分析仪(MLA)、扫描电镜(SEM)、X射线衍射(XRD)研究了紫金山金铜矿入选矿石中有价元素铜、金、银的赋存状态以及分选过程中的金属走向。结果表明,铜矿物主要有蓝辉铜矿、铜蓝、硫砷铜矿,金银以游离矿物和硫化物包裹体为主。铜矿物常见沿明矾石溶蚀孔洞或碎裂缝隙充填,与黄铁矿密切连生,从原矿中分选铜矿物,理论品位为Cu 69.70%,理论回收率93.55%。中粒金嵌布于铜矿物和黄铁矿矿物粒间或裂隙,可随着铜和硫的回收进入铜、硫精矿,金的理论回收率分别为57.19%和27.27%;微细金粒包裹于明矾石和石英中,随脉石损失于尾矿中。银以显微银为主,多见呈微细粒包裹于硫化矿物中,铜精矿和硫精矿中银的理论回收率分别为56.96%和26.71%。

Study on occurrences of copper, gold and silver in Zijinshan Cu-Au deposit

The occurrences of the valuable elements copper, gold and silver in Zijinshan Cu-Au deposit ore and their trends in the separation process were studied by using MLA, SEM and XRD techniques. It was shown that copper minerals mainly included chalcocite, covellite, enargite, etc., and that gold and silver minerals existed as dissociate minerals and sulfide inclusions. Copper minerals were commonly filled along dissolution holes or broken cracks of alunite, closely associated with pyrite. Separating copper minerals from the original ore, the theoretical grade was Cu 69.70%, and the theoretical recovery rate was 93.55%. Medium-grained gold embedded between grains or cracks of copper minerals and pyrite minerals, was obtained from copper and sulfur concentrates, and the theoretical recovery rates of gold in copper and sulfur concentrates were 57.19% and 27.27%, respectively. Fine gold particles were encapsulated in alunite and quartz, and lost in tailings along with gangue. Silver was dominated by microscopic silver, and it was mostly wrapped in sulfide minerals. The theoretical recovery rates of silver in copper and sulfur concentrates were 56.96% and 26.71%, respectively.