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A black, red-brown, or colorless mineral, essentially (Fe, Mn)(Nb, Ta)2O6, the principal ore of niobium.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(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]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
a black mineral, mainly iron niobate, (Fe, Mn)Nb2O6, the chief ore of niobium.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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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
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