Lapis Lazuli

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Lapis Lazuli
Chemical composition rock consisting of lazurite, hauyne, calcite and pyrite
Habit aggregate
Fracture uneven
Hardness 5.5
Refractive index 1.500 - 1.670
Specific gravity 2.50 - 3.00
Lustre resinous to vitreous
Lapis Lazuli with Pyrite inclusions


Common enhancements to lapis lazuli:

  • Fracture filling - wax (with dye or withou) - conceal cracks and fractures and to improve luster
  • Dye - color staining - to produce evenly colored material


Untreated lapis lazuli cabochon from Afghanistan.
Image courtesy of Scott Davies.