/keuh lum"buyt/, n.
a black, crystalline mineral, iron niobate, (Fe, Mn)Nb2O6, the principal ore of niobium, an end member of a series of solid solutions in which manganese and tantalum combine to form tantalite.
[1795-1805; COLUMB(IUM) + -ITE1]

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 hard, black (often iridescent), heavy oxide mineral of iron, manganese, and niobium [(Fe,Mn)Nb2O6]. tantalum atoms replace niobium atoms in the crystal structure to form the mineral tantalite, which is similar but much more dense. These minerals are the most abundant and widespread of the naturally occurring niobates and tantalates and are important ores, their elements niobium and tantalum serving as constituents of corrosion-resistant metal alloys. Columbite and tantalite are found together in granite, pegmatites, and placer deposits. They occur abundantly in western Australia, Madagascar, and South Dakota, U.S. The element niobium (formerly called columbium) was first recognized in columbite and originally was named after the mineral. For detailed physical properties, see oxide mineral (table).

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Universalium. 2010.

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Look at other dictionaries:

  • Columbite — (Fe) General Category Oxide minerals Chemical formula Fe2+Nb2O …   Wikipedia

  • Columbite — Co*lum bite, n. [Cf. F. colombite. See {Columbium}.] (Min.) A mineral of a black color, submetallic luster, and high specific specific gravity. It is a niobate (or columbate) of iron and manganese, containing tantalate of iron; first found in New …   The Collaborative International Dictionary of English

  • columbite — [kə lum′bīt΄] n. [ COLUMB(IUM) + ITE1] a black, orthorhombic mineral, (Fe,Mn)(Nb,Ta) 2O6, that is an ore of niobium and tantalum …   English World dictionary

  • columbite — ● colombite ou columbite nom féminin (anglais columbite) Niobotantalate naturel de fer et de manganèse, utilisé comme minerai de niobium (ou colombium). ● colombite ou columbite (synonymes) nom féminin (anglais columbite) Niobotantalate naturel… …   Encyclopédie Universelle

  • columbite — kolumbitas statusas T sritis chemija apibrėžtis Mineralas. formulė (Fe,Mn)(Nb,Ta)₂O₆ atitikmenys: angl. columbite; niobite rus. колумбит; ниобит ryšiai: sinonimas – niobitas …   Chemijos terminų aiškinamasis žodynas

  • columbite — noun Etymology: New Latin columbium Date: 1805 a black mineral consisting mostly of iron and niobium …   New Collegiate Dictionary

  • columbite — noun A black mineral that is a mixed iron and manganese niobate and tantalate, and is the main ore of niobium and tantalum See Also: columbium …   Wiktionary

  • columbite — co·lum·bì·te s.f. TS mineral. minerale raro di colore nero, costituito da ossido di ferro, manganese, niobio e tantalio, principale fonte di questi ultimi due metalli {{line}} {{/line}} DATA: 1892 …   Dizionario italiano

  • columbite — pl.f. columbiti …   Dizionario dei sinonimi e contrari

  • columbite — [kə lʌmbʌɪt] noun a black mineral consisting of an oxide of iron, manganese, niobium, and tantalum. Origin C19: from columbium + ite1 …   English new terms dictionary

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