The sodalite group is a mineral group of feldspathoid minerals with a zeolitic crystal structure similar to that of the eponymous sodalite. In zeolite chemistry, the sodalite structure is abbreviated as SOD.
Structure The primary structure of sodalite-group minerals is a framework of truncated octahedral aluminosilicate "cages" surrounding smaller extra-framework anions and cations that serve to balance the charge. Specific ions are characteristic of specific members of the group, with partial substitution giving rise to varities such as hackmanite.
Members The sodalite group includes the following minerals: Haüyne — Sodalite — Nosean — Lazurite — Tsaregorodtsevite — Tugtupite — Vladimirivanovite —
The characteristic blue color of sodalite-group minerals arises mainly from caged and clusters.
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