西藏邦布金矿为一处典型的碰撞造山型金矿,成矿主要与区域内巨厚石英脉密切相关。矿床主要发育四期成矿阶段:石英-粗粒硫化物阶段、金-细粒硫化物阶段、碳酸盐阶段和胶黄铁矿阶段,前两个阶段为主要金成矿阶段。通过手标本样品统计、显微镜观察、电子探针扫描等综合技术对金矿石中金的赋存状态进行了研究。结果表明,金主要以独立矿物相存在,自然金成色为750~931,Au/Ag为11.3~17.6。矿石中金的粒度以细粒金、微粒金为主。主要赋金矿物有石英、黄铁矿、黄铜矿、方铅矿和闪锌矿等,自然金主要呈裂隙金、包裹金形式嵌布在硫化物和石英中。
The Bangbu deposit is a typical orogenic gold deposit in the Jiacha area, southern Tibet. Gold mineral- ization in this deposit is mainly associated with lode quart-veins, which can be further divided into two stages, in- cluding the pyrite-quartz veins and the gold-quartz-pyrite veins. Gold is mainly oecurred as independent mineral grains, and they are mainly hosted in the crystals of quartz, pyrite, chalcopyrite and galena, with minor of them in the cracks of these minerals. Gold grains are dominated by micrometer to mustard size.