国内外地下采矿技术的发展很快,工艺装备和方法的更新周期不断缩短,矿石的损失贫化和生产成本逐日降低,经济效益显著提高。桥口铅锌矿在此期间,也由一个土法开采的小有色金属矿山,发展为中型矿山, The development of underground mining technology both at home and abroad has been developing rapidly. The renewal cycle of process equipment and methods has been continuously shortened. The loss and depletion of ore and the cost of production have been reduced day by day, and the economic benefits have been remarkably improved. During this period, Qiaokou Pb-Zn mine was also developed into a medium-sized mine by a small nonferrous metal mine mined by indigenous technologies.