Sodalite, a blue frame-like silicate mineral, is widely used as a decorative gem. Although the bulk of sonarite is mostly opaque, the crystals are usually transparent to translucent.
Sodalite is a rich royal blue tectosilicate mineral with the formula Na 8(Al 6Si 6O 24)Cl2, 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, nosean, lazurite and tugtupite.
First discovered by Europeans in 1811 in the llimaussag intrusive complex in Greenland, sodalite did not become important as an ornamental stone until 1891 when vast deposits of fine material were discovered in Ontario, Canada.
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