There is high tantalite grade for certain large scale granite - pegmatite pattern tantalite - columbite mine in our country.我国某大型花岗伟晶岩型铌钽矿含钽品位高居我国钽铌矿山之首.The measurement indicates that the optimized performance can be ach...

columbite的音标：columbite的英式发音音标为：[kə'lʌmbaɪt]columbite的美式发音音标为：[kə'lʌmbaɪt]...

n.钶铁矿...