Zeolite

Zeolite is not a single mineral but the name of a large group of natural minerals: hydrated framework aluminosilicates of alkali and alkaline-earth metals whose structure contains open channels and cages holding water and exchangeable cations. About 40 natural zeolites are known, and many more have been synthesised for industry. Material sold simply as "zeolite" (usually white) does not, by that name alone, tell which zeolite species it is.