Composition: (Mg,Fe)2SiO4
crystal System:  Orthorombic
Habit: Prismatic although complete crystals are rare
Refractive Index: 1.65-1.69
Double Refraction and Optic Sign: 0.036 positive  (neative at Fayalite end of Isomorphous series)
Hardness: 6.5
Cleavage:
  Poor
Fracture: Conchoidal
Lustre:  Vitreous
Pleochroism: Weak (Green, yellowish green)
Absorption Spectrum: Three bands in the blue
Inclusions: Chromite crystals producing flat stress cracks termed "lily pads", micas flakes and minute bubble like droplets
Occurrence:  Main source is Zeberget in the red sea, UIpper Mayanmar (Burma), Austraia, Brazil, Chian, Mexixo,Norway,USA

Peridot

John Cadby Jewellers
 Goldsmith, Silversmith,
Diamond Merchants, Appraiser & Engraver.
**************************************************************************
3, White Hart Yard, Trowbridge, Wiltshire.  BA14 8BY
Tel: 01225 776322  E-Mail: John@Cadby.co.uk

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