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Adularia

  • Etymology : From the greek "Adula"
  • Discovery: 1780 by Ermenegildo Pini
  • Type localityAdula, it is the ancient Latin name of Mont Saint Gothard in Switzerland.

To learn more about the mineralogy of the adularia, see Mindat.ord

Gemological data

  • Chemical formula : KAlSi3O8
  • Hardness (Mohs) : 6 - 6.5
  • Density : 2.56 - 2.628
  • Refractive index : 1,518 - 1,539
  • Birefingence : -0,008
  • Crystal system : Monoclinic
  • Group : Feldspars - Tectosilicates
  • Mineralogical Class : Silicates

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