Sodalite

Sodalite is a natural mineral, a sodium aluminium silicate with chlorine (Na₄Al₃Si₃O₁₂Cl) of the sodalite group, also classed as a feldspathoid; its name refers to its sodium content. As a gem it is usually massive, light to dark rich blue, often veined with white calcite. It belongs to the same mineral group as haüyne, lazurite and nosean, the blue minerals that principally make up the rock lapis lazuli, but sodalite itself is a single mineral.