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Sodalite is a rich royal blue mineral widely enjoyed 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. Discovered in 1811 in Greenland, sodalite did not become important as an ornamental stone until 1891 when vast deposits of fine material were discovered in Ontario, Canada.

A light, relatively hard yet fragile mineral, sodalite is named after its sodium content. Well known for its blue color, sodalite may also be gray, yellow, green, or pink and is often mottled with white veins or patches. The more uniformly blue material is used in jewelry, where it is fashioned into cabochons and beads. Lesser material is more often seen as facing or inlay in various applications.

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Although somewhat similar to lazurite and lapis lazuli, sodalite rarely contains pyrite (a common inclusion in lapis) and its blue color is more like traditional royal blue rather than ultramarine. It is further distinguished from similar minerals by its white (rather than blue) streak.

Significant deposits of fine material are restricted to but a few locales: Bancroft, Ontario, and Mont-Saint-Hilaire, Quebec, in Canada; and Litchfield, Maine, and Magnet Cove, Arkansas, in the USA. The Ice River complex, near Golden, British Columbia, also contains sodalite. Smaller deposits are found in South America (Brazil and Bolivia), Portugal, Romania, Burma and Russia. Hackmanite, an important variety of sodalite is found principally in Mont-Saint-Hilare and Greenland. Euhedral, transparent crystals are found in northern Namibia and in the lavas of Vesuvius, Italy.