The size of these channels controls the size of the molecules or ions, and therefore a zeolite like analcime can act as a chemical sieve. Color is clear, white or gray, with greenish, yellowish and reddish tints possible. Luster is vitreous. Also granular and massive. Cleavage is absent.
Fracture is uneven.
Hardness is 5 - 5.5. Streak is white. Associated Minerals are quartz , calcite , serandite , apophyllite , natrolite , stilbite , heulandite and other zeolites . Best Field Indicators are crystal habit, density, low hardness, luster and associations.