Topaz

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Topaz
TopazUSGOV.jpg
A group of topaz crystals on matrix
General
Category Silicate mineral
Chemical formula Al2SiO4(F,OH)2
Identification
Color Colorless (if no impurities), blue, brown, orange, gray, yellow, green, pink and reddish pink
Mohs Scale hardness 8 (defining mineral)
Luster Vitreous
Birefringence δ = 0.010
References [1][2][3][4]

Topaz is a rock. It includes the minerals aluminium and fluorine with the chemical formula Al2SiO4(F,OH)2.

Color and varieties[change | edit source]

Pure topaz is colorless and transparent but they usually have colors. The typical topaz is wine, yellow, pale gray, reddish-orange, or blue brown. It can also be made white, pale green, blue, gold, or pink (rare).

Orange topaz, also known as precious topaz, is the traditional November birthstone, the symbol of friendship, and the state gemstone for the US state of Utah.[5]

Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Some imperial topaz stones can fade if they are exposed too much in the sunlight.[6][7]

Blue topaz is the US state Texas' gemstone.[8]

Mystic topaz is colorless topaz which has been artificially coated, making it rainbow-colored.[9]

Gallery[change | edit source]

References[change | edit source]

  1. Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., ISBN 0-471-80580-7
  2. Topaz. Handbook of Mineralogy. (PDF) . Retrieved on 2011-10-29.
  3. Topaz. Mindat.org. Retrieved on 2011-10-29.
  4. Topaz. Webmineral.com. Retrieved on 2011-10-29.
  5. Utah State Gem – Topaz. Pioneer.utah.gov (2010-06-16). Retrieved on 2011-10-29.
  6. Imperial Topaz, Natural History Museum of Los Angeles County
  7. Gemstones & Gemology – Topaz, Emporia State University
  8. State Gem – Texas Blue Topaz. State Gemstone Cut – Lone Star Cut. state.tx.us
  9. Mystic Topaz, Consumer Information. Farlang.com (2008-10-30). Retrieved on 2011-10-29.

Other pages[change | edit source]

Other websites[change | edit source]