Citrine

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Pendant with citrine
MFA# 39.764

Description

A pale yellow to red-orange Quartz Gemstone that contains trace Iron impurities. Citrine is found in western Europe, Scotland, Brazil, Uruguay, Africa, Malagasy Republic, Madagascar, Sri Lanka, the Urals, and the United States. Many ancient citrines have been incorrectly identified as Topaz. Currently, most gems sold as citrine are actually heat-treated amethysts. Ametrine is a stone that contains both citrine and amethyst, i.e. zones of purple and yellow.

Citrine crystal

Synonyms and Related Terms

Faceted ametrine
from Wikipedia

Madeira topaz; ametrine (bicolor yellow/lavender); false topaz; Spanish topaz; Occidental topaz; topaz quartz; Citrin (Deut.); citrine (Fr.); cytryn (Pol.); citrino (Esp., Port.); citrien (Ned.)

Raman purple (MFA)

Ametrine, purple, 785, 100.TIF

Raman yellow (MFA)

Ametrine, yellow, 785, 100.TIF

FTIR (MFA)

Quartz.TIF


Physical and Chemical Properties

  • Trigonal crystal system
  • Low thermal expansion
  • Fracture = conchoidal
  • Luster = vitreous to greasy
  • Streak = white
  • Fluorescence = generally inert
  • Pleochroism = very weak with tone of yellow-orange in yellow ; weak to moderate reddish purple in purple
  • Can be piezoeletric and/or triboluminescent
Composition SiO2
Mohs Hardness 7.0
Density 2.65 g/ml
Refractive index 1.544 - 1.553
Birefringence 0.009

Comparisons

Properties of Common Gemstones

Resources and Citations

  • Gem Identification Lab Manual, Gemological Institute of America, 2016.
  • Mineralogy Database: Quartz
  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 646
  • Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
  • Encyclopedia Britannica, http://www.britannica.com Comment: "citrine." Accessed: 7 Apr. 2005 .
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • Wikipedia: Citrine (Accessed Sept. 7, 2005 and Dec 2022)
  • Thomas Gregory, The Condensed Chemical Dictionary, Reinhold Publishing, New York, 3rd ed., 1942
  • Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
  • Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
  • The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998