Source : Webster's Revised Unabridged Dictionary (1913)

Sodalite \So"da*lite\, n. [Soda + -lite: cf. F. sodalithe.]
   (Min.)
   A mineral of a white to blue or gray color, occuring commonly
   in dodecahedrons, also massive. It is a silicate of alumina
   and soda with some chlorine.

Source : WordNet®

sodalite
     n : a vitreous mineral consisting of sodium aluminum silicate
         and sodium chloride in crystalline form; occurs in
         igneous rocks