矿物浓缩 meaning in English

upgrading of mineral

Standard practice for proof silver corrections in metal bearing ores , concentrates and related materials by fire assay gravimetry
用火试金重量分析法验证含金属矿物浓缩物及相关材料中银修正值的标准实施规范
Standard practice for fire assay silver corrections in analysis of metal bearing ores , concentrates , and related metallurgical materials by silver determination in slags and cupels
用炉渣和灰吹盘中的银测定法在含金属矿物浓缩物及相关冶金材料的分析中测定火试金法银修正值的标准实施规范