Category Zeolite minerals Dana classification 77.1.3.1 Space group P21/n | Formula
(repeating unit) CaAl2Si2O8·4(H2O) Crystal system Monoclinic | |
 | ||
Crystal class Prismatic (2/m)
(same H-M symbol) | ||
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.
References
Gismondine Wikipedia(Text) CC BY-SA