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A black, red-brown, or colorless mineral, essentially (Fe, Mn)(Nb, Ta)2O6, the principal ore of niobium.
(Minerals) a black mineral consisting of a niobium oxide of iron and manganese in orthorhombic crystalline form: occurs in coarse granite, often with tantalite, and is an ore of niobium. Formula: (Fe, Mn)(Nb)2O6. Also called: niobite
[C19: from columbium + -ite1]
a black mineral, mainly iron niobate, (Fe, Mn)Nb2O6, the chief ore of niobium.
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|Noun||1.||columbite - a black mineral that is an ore of niobium and tantalum|
atomic number 41, Nb, niobium - a soft grey ductile metallic element used in alloys; occurs in niobite; formerly called columbium
atomic number 73, Ta, tantalum - a hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite
mineral - solid homogeneous inorganic substances occurring in nature having a definite chemical composition