Permutite

any artificial aluminosilicate that resembles a natural zeolite in chemical composition and properties. Permutites have the general formula Na₂O• Al₂O₃-nSiO₂-mH₂O, where n varies from 1 to 10, and m from 1 to 2. They are capable of ion exchange and are used as inorganic ion exchangers for softening water. The term “permutite” is also applied to certain synthetic ion-exchange resins produced outside the USSR.