Lévyne

Formula: (Ca,Na2)3(Si12Al6)O36.18H2O tectosilicate (framework silicate), zeolite group
Specific gravity: 2.09 to 2.16
Hardness: 4 to 4½
Streak: White
Colour: Colourless, white, grey, yellow, red
Environments:

Basaltic cavities

Lévyne occurs most commonly in cavities in low silica volcanic rocks such as olivine basalt, and rarely in andesite, often associated with other zeolites, especially offretite and erionite.