Minerals tuaj yeem siv rau hauv engineering xws li hlau mines, metallurgical kev lag luam, tshuaj lom neeg kev lag luam, kev tsim kho kev lag luam, railway (txoj kev) txoj kev siv chav tsev, cement kev lag luam thiab xuab zeb thiab gravel kev lag luam.Raws li cov khoom siv hluav taws xob sib txawv, muaj cov mining sib txawv.Cov no ...
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