Sodalite

Unpolished and uncut sodalite.

Sodalite is a feldspar-like zeolite mineral. It was the first discovered member of the sodalite mineral group, which also includes lazurite. Sodalite is used as a gemstone for its dark blue colour.

Structure

Sodalite's crystal structure is made up of silicate "cages" that hold ions inside them.

Like other zeolites, sodalite has a cage-like crystal structure. Sodalite's "cages" contain mostly sodium and chlorine.^[1]

A sample of sodalite-carbonate pegmatite from Bolivia, with a polished rock surface.
Hackmanite dodecahedron from the Koksha Valley, Afghanistan
Hippo in sodalite, length 9 cm (3.5 in)

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