التعدين والمحاجر في نيجيريا
مكونات صناعة التعدين في نيجيريا. Mining industry of Nigeria Wikipedia. The mining of minerals in Nigeria accounts for only 03% of its [GDP], due to the influence of its, Columbite and Tantalite are ores used to produce the elements niobium and tantalum Columbite and tantalite are collectively known as coltan in.