scheelite

scheelite
/shay"luyt, shee"-/, n. Mineral.
calcium tungstate, CaWO4, usually occurring in tetragonal crystals: an important ore of tungsten.
[1830-40; < G Scheelit, named after K. W. SCHEELE, who first isolated tungstic acid; see -ITE1]

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      calcium tungstate mineral, CaWO4, that is an important ore of tungsten. It acquired commercial value in the 20th century when tungsten became used in alloy steels and electric-light filaments. The mineral is named in honour of the Swedish chemist Carl Wilhelm Scheele, who obtained tungstic acid from it in 1781. Scheelite commonly occurs as compact or granular masses in contact metasomatic deposits, high-temperature veins, and granite pegmatites. In the United States it has been mined extensively in North Carolina, California, and Nevada. It also occurs in Cornwall and Cumberland in England, and in Bolivia, New South Wales, New Zealand, Siberia, Switzerland, and France.

      Scheelite is white, yellow, brown, or green in colour and has a vitreous to adamantine lustre. Most scheelite fluoresces, the colour ranging from blue-white or white to yellow, depending upon the amount of molybdenum present. The mineral's Mohs hardness is 4.5–5; specific gravity, 5.9–6.1; and crystal system, tetragonal. Scheelite is one end-member of a continuous series of solid solutions in which the second component is the similar mineral powellite, CaMoO4.

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Universalium. 2010.

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Look at other dictionaries:

  • Scheelite — [1] Catégorie VII : sulfates, sélénates tellurates, chromates, molybdates, tungstates[2] …   Wikipédia en Français

  • Scheelite — Scheel ite, n. [From C.W. Scheele, a Swedish chemist.] (Min.) Calcium tungstate, a mineral of a white or pale yellowish color and of the tetragonal system of crystallization. [1913 Webster] …   The Collaborative International Dictionary of English

  • scheelite — ● scheelite nom féminin (de C. W. Scheele, nom propre) Tungstate naturel de calcium, de formule CaWO4, du système quadratique, constituant un minerai de tungstène …   Encyclopédie Universelle

  • scheelite — s. f. [Mineralogia] Tungstato natural de cálcio, de fórmula CaWO4, do sistema tetragonal, que pode originar um minério de tungstênio. (Deve se a sua descoberta a Scheele, que descobriu o tungstênio.)   ♦ Grafia no Brasil: scheelita …   Dicionário da Língua Portuguesa

  • scheelite — [shā′līt΄, shē′līt΄] n. [Ger scheelit, after K. W. Scheele (1742 86), Swed chemist] a yellowish white to brown, hard mineral, calcium tungstate, CaWO4, that is an ore of tungsten …   English World dictionary

  • Scheelite — Infobox mineral name = Scheelite category = boxwidth = boxbgcolor = caption = formula = Calcium tungstate CaWO4 molweight = color = Golden yellow, brownish green, brown, pinkish to reddish gray, colorless habit = Pseudo octahedra, massive,… …   Wikipedia

  • scheelite — šelitas statusas T sritis chemija apibrėžtis Mineralas. formulė CaWO₄ atitikmenys: angl. scheelite rus. шеелит …   Chemijos terminų aiškinamasis žodynas

  • scheelite — n. Mineral. calcium tungstate in its mineral crystalline form. Etymology: K. W. Scheele, Sw. chemist d. 1786 * * * scheelite Min. (ˈʃiːlaɪt) [f. the name of K. W. Scheele, the discoverer of tungstic acid + ite.] Tungstate of calcium, found in… …   Useful english dictionary

  • scheelite — noun Etymology: German Scheelit, from Karl W. Scheele died 1786 Swedish chemist Date: circa 1837 a mineral consisting of the tungstate of calcium that is an ore of tungsten …   New Collegiate Dictionary

  • scheelite — noun A mineral composed of calcium tungstate, with the chemical formula CaWO; an important tungsten ore …   Wiktionary

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