Sodalite

Sodalite is a rich royal blue tectosilicate mineral with the formula Na 8(Al 6Si 6O 24)Cl 2, widely used as an ornamental gemstone. Although massive sodalite samples are opaque, crystals are usually transparent to translucent. Sodalite is a member of the sodalite group with hauyne and tugtupite.

First discovered by Europeans in 1811 in the Ilimaussaq intrusive complex, sodalite did not become important as an ornamental stone until 1891 when vast deposits of fine material were discovered in Ontario , Canada.