Gismondine

Gismondine
Gismondine, Campo de Calatrava, Ciudad Real, Spain
General
CategoryZeolite minerals
Formula
(repeating unit)
CaAl2Si2O8·4(H2O)
Dana classification77.1.3.1
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/n

Gismondine is a mineral with the chemical formula CaAl2Si2O8·4(H2O). It is a zeolite or hydrated alumino-silicate. It forms colorless, bipyramidal crystals of orthorhombic symmetry.

Gismondine was named for Italian mineralogist Carlo Giuseppe Gismondi (1762–1824). It has been found in Iceland, Ireland, and Italy.