Lapis Lazuli

Scientific Name: Lazurite

Group: Silicates – tectosilicates

Chemical composition: Na3Ca(Al3Si3O12)S

Colors: Various intense shades of blue.

Hardness: 5 to 5.5

Formation: Cubic crystals

Principal Sources: Afghanistan, Italy, Argentina, US, Tajikistan.

Special Notes: The best quality is intense dark blue, with patches of white calcite and yellow pyrite. Lapis was used as a gemstone for thousands of years by Egyptians. Powdered lapis was used to make the pigment ultramarine.