What is "gismondine"

Gismondine \Gis*mon"dine\, Gismondite \Gis*mon"dite\, n. [From the name of the discoverer, Gismondi.] (Min.) A native hydrated silicate of alumina, lime, and potash, first noticed near Rome.

n. (context mineral English) A zeolite mineral with the chemical formula CaAl₂Si₂O₈·₄(H₂O).

Gismondine is a mineral with the chemical formula CaAlSiO·4(HO). 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.