turquoise

turquoise
/terr"koyz, -kwoyz/, n.
1. Also, turquois. an opaque mineral, a basic hydrous copper aluminum phosphate often containing a small amount of iron, sky-blue or greenish-blue in color, cut cabochon as a gem. Cf. bone turquoise.
2. Also called turquoise blue. a greenish blue or bluish green.
[1350-1400; < F: Turkish (stone), equiv. to Turc TURK + -oise, fem. of -ois -ESE; r. ME turkeis < MF]

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Hydrated copper and aluminum phosphate mineral, CuAl6(PO4)4(OH)8 · 5H2O, that is used extensively as a gemstone.

The colour of turquoise ranges from blue through various shades of green to greenish and yellowish gray. A delicate sky-blue, which provides an attractive contrast with precious metals, is most valued for gem purposes. Numerous deposits of turquoise in the southwestern U.S. have been worked for centuries by American Indians. The mineral also occurs in Iran, northern Africa, Australia, and Siberia.

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 hydrated copper and aluminum phosphate [CuAl6(PO4)4(OH)8·4H2O] that is extensively used as a gemstone. It is a secondary mineral deposited from circulating waters, and it occurs chiefly in arid environments as blue to greenish, waxy veinlets in alumina-rich, weathered, volcanic, or sedimentary rocks. Turquoise was obtained from the Sinai Peninsula before the 4th millennium BC in one of the world's first important hard-rock mining operations. It was transported to Europe through Turkey, probably accounting for its name, which is French for “Turkish.” Highly prized turquoise has come from Neyshābūr, Iran. Numerous deposits in the southwestern United States have been worked for centuries by American Indians. Turquoise also occurs in northern Africa, Australia, Siberia, and Europe. For detailed physical properties, see phosphate mineral (table).

      The colour of turquoise ranges from blue through various shades of green to greenish and yellowish gray. A delicate sky blue, which provides an attractive contrast with precious metals, is most valued for gem purposes. Delicate veining, caused by impurities, is desired by some collectors as proof of a natural stone. Turquoise is opaque except in the thinnest splinters, takes a fair to good polish, and has a feeble, faintly waxy lustre. The stone's colour and lustre tend to deteriorate with exposure to sunlight, heat, or various weak acids. For most gem uses, turquoise is cut en cabochon, with a low-convex, polished upper surface. It may be carved or engraved, and irregular pieces are often set in mosaics with jasper, obsidian, and mother of pearl. Turquoise matrix, which is any natural aggregate of turquoise with limonite or other substances, is also valued.

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Universalium. 2010.

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  • turquoise — [ tyrkwaz ] n. f. et adj. • XIIIe; de l adj. turquois « turc », var. turquesse, turquesque 1 ♦ Minér. Minéral formé de phosphate hydraté de cuivre et d aluminium, roche non transparente colorée du bleu clair au vert pomme. Gisements de turquoise… …   Encyclopédie Universelle

  • Turquoise — Services Limited Rechtsform Limited Company Gründung 2008 Sitz London Branche Handelssysteme Website …   Deutsch Wikipedia

  • Turquoise B&B — (Монреаль,Канада) Категория отеля: 3 звездочный отель Адрес: 1576 Rue Alexandre de Sèv …   Каталог отелей

  • Turquoise — Tur*quoise , Turquois Tur*quois (?; 277), n. [F. turquoise; cf. Pr. & Sp. turquesa, It. turchese, turchina, LL. turchesius, turchina; so called because first brought from Turkey. See 1st {Turkey}.] (Min.) A hydrous phosphate of alumina containing …   The Collaborative International Dictionary of English

  • Turquoise — Tur*quoise , a. Having a fine light blue color, like that of choice mineral turquoise. [1913 Webster] …   The Collaborative International Dictionary of English

  • turquoise — Turquoise. sub. f. Pierre precieuse de couleur bleuë, & qui n est point transparente. Turquoise de la vieille roche, de la nouvelle roche …   Dictionnaire de l'Académie française

  • turquoise — [tʉr′koiz΄, tʉr′kwoiz΄] n. [ME turkeis < MFr turqueise, fem. of OFr turqueis, Turkish (see TURK1): orig. brought to western Europe through Turkey] 1. a greenish blue, hard mineral, hydrous copper aluminum phosphate, CuAl6 (PO4) 4 (OH) 8·5H2O,… …   English World dictionary

  • Turquoise — (spr. Türkoahs), berkanartiger gegatterter od. gestreifter Zeug …   Pierer's Universal-Lexikon

  • turquoise — precious stone, 1560s, replacement from M.Fr. of M.E. turkeis, turtogis (late 14c.), from O.Fr. turqueise, fem. adj. Turkish, in pierre turqueise Turkish stone, so called because it was first brought to Europe from Turkestan or some other Turkish …   Etymology dictionary

  • turquoise — The recommended pronunciation in BrE is tur kwoiz, but a more French like form tur kwahz is sometimes heard …   Modern English usage

  • turquoise — ► NOUN 1) a semi precious stone, typically opaque and of a greenish blue or sky blue colour. 2) a greenish blue colour. ORIGIN Old French turqueise Turkish stone …   English terms dictionary

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