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topaz
topaz , aluminum silicate mineral with either hydroxyl radicals or fluorine, Al 2 SiO 4 (F,OH) 2 , used as a gem. It is commonly colorless or some shade of pale yellow to wine-yellow; pale blue and pale green also occur, but natural red stones are uncommon. Some natural yellow stones lose their yellow coloring when heated and become permanently pink ( "pinked" topaz). The stone is transparent with a vitreous luster. It has perfect cleavage on the basal pinacoid, but it is nevertheless hard and durable. The brilliant cut is commonly used. Topaz crystals, which are of the orthorhombic system, occur in highly acid igneous rocks, e.g., granites and rhyolites, and in metamorphic rocks, e.g., gneisses and schists. Important sources of topaz are in Russia, Siberia, Brazil, Australia, and Mexico and in New Hampshire, Colorado, and Utah in the United States. The name topaz is commonly but incorrectly used for various other yellow stones, e.g., for citrine quartz . |
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"topaz." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "topaz." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1E1-topaz.html "topaz." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-topaz.html |
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topaz
topaz A nesosilicate mineral, Al2SiO4(OH,F)2; sp. gr. 3.5–3.6; hardness 8; orthorhombic; colourless, pale yellow, pale blue, yellowish, or sometimes pink; often transparent; vitreous lustre; crystals are prismatic and often bipyramidal with the vertical faces striated, but it can also be massive and granular; cleavage perfect basal orthorhombic; typically occurs in granite pegmatites, rhyolite, and quartz veins, and extensively as an accessory mineral in granites, associated with fluorite, tourmaline, beryl, and cassiterite, also in alluvial deposits. It is associated with pneumatolytic action (see PNEUMATOLYSIS) and is a constituent of greisen. The original cairngorms (see QUARTZ) were topaz crystals. It is named after Topazos Island in the Red Sea.
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AILSA ALLABY and MICHAEL ALLABY. "topaz." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "topaz." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O13-topaz.html AILSA ALLABY and MICHAEL ALLABY. "topaz." A Dictionary of Earth Sciences. 1999. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-topaz.html |
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topaz
to·paz / ˈtōpaz/ • n. 1. a precious stone, typically colorless, yellow, or pale blue, consisting of a fluorine-containing aluminum silicate. ∎ a dark yellow color. 2. a large tropical American hummingbird (genus Topaza) with a yellowish throat and a long tail. |
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"topaz." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "topaz." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O999-topaz.html "topaz." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-topaz.html |
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Topaz
Topaz ♀ One of the rarer examples of the class of modern girls' names taken from vocabulary words denoting gemstones. The topaz gets its name via French and Latin from Greek; it is probably ultimately of Oriental origin. In the Middle Ages this was sometimes used as a boy's name, being taken as a form of Tobias.
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PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Topaz." A Dictionary of First Names. 2006. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Topaz." A Dictionary of First Names. 2006. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O41-Topaz.html PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Topaz." A Dictionary of First Names. 2006. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O41-Topaz.html |
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topaz
topaz Transparent, glassy mineral, aluminium fluosilicate, Al2SiO4(F,OH)2, found in pegmatites. Its crystals are orthorhombic system columnar prisms. Topaz is colourless, white, blue or yellow; some large crystals are of gem quality. Hardness 8; r.d. 3.5.
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"topaz." World Encyclopedia. 2005. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "topaz." World Encyclopedia. 2005. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O142-topaz.html "topaz." World Encyclopedia. 2005. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-topaz.html |
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topaz
topaz precious stone. XIII. ME. topace — OF, topace, (also mod.) topaze — L. topaz(i)us, -ion — Gr. tópazos, -ázion.
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T. F. HOAD. "topaz." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "topaz." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O27-topaz.html T. F. HOAD. "topaz." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-topaz.html |
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topaz
topaz The ninth jewel in the wall of the New Jerusalem (Rev. 21: 20).
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W. R. F. BROWNING. "topaz." A Dictionary of the Bible. 1997. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. W. R. F. BROWNING. "topaz." A Dictionary of the Bible. 1997. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O94-topaz.html W. R. F. BROWNING. "topaz." A Dictionary of the Bible. 1997. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O94-topaz.html |
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topaz
topaz
•Abkhaz, as, Baz, has, jazz, pizzazz, razz, whereas
•Boas, Boaz
•topaz • Shiraz • Alcatraz • razzmatazz
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"topaz." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "topaz." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O233-topaz.html "topaz." Oxford Dictionary of Rhymes. 2007. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-topaz.html |
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