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Garnet andradite

  • Translations : Andradit, Andradiet, Allochroit, Andraditas, Andradyt, Андрадит, Andradita, 钙铁榴石
  • Synonym : Allochroite, Aplome, Jellesite, Rothoffite, Polyadelphine
  • Etymology : José Bonifácio de Andrada e Silva, Brazilian mineralogist.
  • Discovery: 1868 by James Dwight Dana

Variety of garnet which can have diverse colors: green-yellow garnet in yellow - green, garnet brown, grey-brown, colorless garnet, garnet red, garnet brown, brown-red garnet, green garnet.

The andradite forms a series with the grossular and one with the schorlmite.

The most sought and the rarest of the garnets of the variety andradite is the garnet démantoïde.

To know more about the mineralogy of Andradite, see Mindat.org->

Gemological data

  • Chemical formula : Ca3 Fe2 +3 (SiO4)3
  • Hardness (Mohs) : 6.5 - 7
  • Density : 3.8 - 3.9
  • Refractive index : 1.88 - 1.94
  • Crystal system : Cubique
  • Group : Garnet
  • Mineralogical Class : Nesosilicates

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