You can mark you interesting snippets of text that will be available through a unique link in your browser.


zircon

Translation
zircon
/zerr"kon/, n.
a common mineral, zirconium silicate, ZrSiO4, occurring in small tetragonal crystals or grains of various colors, usually opaque: used as a refractory when opaque and as a gem when transparent.
[1785-95; < G Zirkon; see JARGON2]

* * *

Silicate mineral, zirconium silicate, ZrSiO4, the principal source of zirconium.

Zircon is widespread as an accessory mineral in acid igneous rocks; it also occurs in metamorphic rocks and, fairly often, in detrital deposits. It occurs in beach sands in many parts of the world, particularly Australia, India, Brazil, and Florida, and is a common heavy mineral in sedimentary rocks. Gem varieties occur in stream gravels and detrital deposits, particularly in Indochina and Sri Lanka, but also in Myanmar, Australia, and New Zealand. Zircon forms an important part of the syenite of southern Norway and occurs in large crystals in Quebec.

Zircon with quartz from Cheyenne Canyon, Colorado

By courtesy of the Field Museum of Natural History, Chicago; photograph, John H. Gerard
EB Inc.

* * *

 silicate mineral, zirconium silicate, ZrSiO4, the principal source of zirconium. Zircon is widespread as an accessory mineral in felsic igneous rocks; it also occurs in metamorphic rocks and, fairly often, in detrital deposits. It occurs in beach sands in many parts of the world, particularly Australia, India, Brazil, and Florida, and is a common heavy mineral in sedimentary rocks. Gem varieties occur in stream gravels and detrital deposits, particularly in Indochina and Sri Lanka, but also in Myanmar (Burma), Australia, and New Zealand. Zircon forms an important part of the syenite of southern Norway and occurs in large crystals in Quebec. For detailed physical properties, see silicate mineral (table).

      The high refractive index and dispersion of zircon cause it to approach diamond in fire and brilliancy. Several varietal names have been applied to coloured gems. hyacinth (jacinth) includes the clear, transparent red, orange, and yellow varieties. Matura diamond, from Sri Lanka, is clear and colourless, either naturally or made so through heat treatment under oxidizing conditions. The name jargon, like zircon derived from Arabic zargūn, applies to all other colours. A lovely blue stone may be made by heat treatment under reducing conditions.

* * *


Universalium. 2010.

  
Share  

Look at other dictionaries:

  • ZIRCON — ZIRC Mot composé à partir du persan, zircon signifie or et lumière. Ce minéral fait partie des silicates à tétraèdres, Si4, isolés (nésosilicates) qui cristallisent, dans le système quadratique, en donnant des formes bitétragonales. Les cristaux… …   Encyclopédie Universelle

  • Zircon — ir con, n. [F., the same word as jargon. See {Jargon} a variety of zircon.] 1. (Min.) A mineral consisting predominantly of zirconium silicate ({Zr2SiO4}) occurring in tetragonal crystals, usually of a brown or gray color. It consists of silica… …   The Collaborative International Dictionary of English

  • zircon — noun min. циркон …   Англо-русский словарь Мюллера

  • zircon — 1> мин. циркон …   Новый большой англо-русский словарь

  • Zircon — Not to be confused with zirconia or cubic zirconia. This article is about the mineral. For other uses, see Zircon (disambiguation). Zircon Zircon crystal from Tocantins, Brazil (2×2 cm) …   Wikipedia

  • Zircon — Pour les articles homonymes, voir Hyacinte (homonymie). Cet article possède un paronyme, voir : Zircone …   Wikipédia en Français

  • zircon — ˈzə:kɔn сущ.; минер. циркон (минералогия) циркон zircon мин. циркон …   Большой англо-русский и русско-английский словарь

  • zircon — noun a) A mineral occurring in tetragonal crystals, usually of a brown or grey colour and consisting of silica and zirconia. b) A crystal of zircon, sometimes used as a false gemstone …   Wiktionary

  • zircon — noun Etymology: German Date: 1794 a tetragonal mineral consisting of a silicate of zirconium and occurring usually in brown or grayish square prisms of adamantine luster or sometimes in transparent forms which are used as gems …   New Collegiate Dictionary

  • zircon — m мин. циркон, ортосиликат циркония …   Большой французско-русский и русско-французский словарь