For reasons that leadconcentrate contains many kinds of metal ores, it is difficult to evaluate its quality grade.
由于铅精矿中含有多种金属矿,给铅精矿质量等级的评价带来很大困难。
3
Processing tests on mixed copper and leadconcentrate produced by a large copper mine in Yunnan Province were carried out aiming at the separation of copper and lead.