Coltan

Tantalum-niobium ore

Coltan (short for columbite–tantalite and known industrially as tantalite) is a dull black metallic ore from which the elements niobium and tantalum are extracted. The niobium-dominant mineral in coltan is columbite (after niobium's original name columbium), and the tantalum-dominant mineral is tantalite. Among other uses, tantalum from coltan is used to manufacture tantalum capacitors which are used for mobile phones, personal computers, automotive electronics, and cameras.

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