某金矿床位于坦桑尼亚太古代绿岩带中，属于脉状构造蚀变岩型矿床。工艺矿物学研究结果表明：矿石含金5.17 g/t，砷0.43 %，硫2.50 %，主要金属矿物有黄铁矿、毒砂、磁铁矿、菱铁矿，脉石矿物主要有石英、长石、碳酸盐、绿泥石、黑云母、黏土矿物；金矿物主要为自然金，载金矿物主要为黄铁矿、毒砂和石英；金矿物嵌布状态以包裹金和粒间金为主，分别为49 %和47 %，裂隙金较少；金矿物粒度非常细小，以微、细粒金为主，占92.5 %。针对该矿石性质，进行了选矿工艺探索试验研究，结果表明：采用重选、全泥氰化浸出和浮选等单一流程，金回收率较低；为进一步提高金浮选指标，进行了磨矿细度、捕收剂、活化剂、起泡剂等药剂制度和流程结构优化试验，确定采用浮选＋尾矿浸出工艺流程。结果表明：在最佳条件下，浮选闭路流程金精矿金品位44.70 g/t，金回收率83.56 %；浮选尾矿氰化金作业回收率34.41 %，金总回收率89.22 %。

A gold deposit in the Tanzanian Archean greenstone belt belongs to the vein-type altered rock deposit.The results of process mineralogy research show that the ore contains 5.17 g/t of gold,0.43 % of arsenic,and 2.50 % of sulfur,and the main metallic minerals are pyrite,arsenopyrite,magnetite,and siderite.The gangue minerals are mainly quartz,feldspar,carbonate,chlorite,biotite,and clay minerals.The main gold mineral is native gold,and the main gold-bearing minerals are pyrite,arsenopyrite,and quartz.The gold mineral distribution is mainly related to encased gold and intergranular gold,with contents of 49 % and 47 %,respectively,and there is less fissure gold.The particle size of gold mineral is very fine,mainly composed of micro and fine-grained gold,accounting for 92.5 %.Based on the properties of the ore,exploration and testing of the ore-dressing process were carried out.The results show that the gold recovery rate is low when using a single process such as gravity separation,all-sliming cyanide leaching,and flotation.To improve the flotation index,experiments were carried out to optimize the reagent regime including grinding fineness,collector,activator and frother,and the process structure,and it was determined to use the flotation＋tailings leaching process.The results show that under the optimal conditions,the gold grade of  gold concentrates in the closed-circuit flotation process is 44.70 g/t,the gold recovery rate is 83.56 %;the cyanidation gold operational recovery rate in the flotation tailings is 34.41 %,and the total gold recovery rate is 89.22 %.