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Alexandrite

Alexandrite
  • Translations : Alejandrita, Aleksandriidina, Aleksandriitti, Aleksandritas, Aleksandryt, Alessandrite, Alexandriet, Alexandrit, Alexandrita, Alexandrite, Александрит, アレキサンドライト, 亞歷山大石. 金緑石
  • Synonym : Diaphanite
  • Etymology : Its name was given in honor of the Russian Tsar Alexander II. According to legend, the first discovery was in the Ural mountains on the day of his birth.
  • Discovery: 1842 by Nils Adolf Erik Nordenskiöld
  • Type localityUral - Russia

The Alexandrite is a very rare stone. Its originality is its change of color according to the wavelength of the light source. If it is the sunlight or a fluorescent lamp, the stone will be green. If the light source is an incandescent lamp, the stone will be violet to red.

The color of the alexandrite is coming from chromium.

Synthetic "alexandrite effect" corundons have been created. They are often sold as natural alexandrites and often at high prices.

Tourists, take care! There is no natural Alexandria in Alexandria in Egypt ...Natural Alexandrite is one of the rarest gemstones. Its price is therefore very high.

 

To learn more about the mineralogy of Alexandrite, see mindat.org ->

See the Alexandrite for sale.

Gemological data

  • Chemical formula : Be(AlO2)2
  • Hardness (Mohs) : 8.58
  • Density : 3.5/3.84
  • Refractive index : np=1.746 / nm=1.748 / ng=1.756
  • Birefingence : +0.008 / +0.011
  • Crystal system : Orthorhombic
  • Group : Chrysoberyl

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