Natrolite
Image: Robert M. Lavinsky (CC BY-SA 3.0)
Mineral NameNatrolite
Chemical FormulaNa2Al2Si3O10·2H2O
Mohs Hardness5
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavageperfect on {110}
Fractureuneven to conchoidal
Specific Gravity2.25
Colorswhite, colorless, pink, yellowish
Transparencytransparent
Type LocalityTick Canyon, Lang, Los Angeles County, California, USA
Mineral GroupZeolite group (Tectosilicates)
Usescollector, adsorbent (minor)
Associated Mineralscalcite, apophyllite, heulandite, stilbite, prehnite
Rarityuncommon
Description
This image displays a cluster of delicate, radiating acicular (needle-like) crystals of Natrolite, predominantly white to colorless, forming a spherical or hemispherical aggregate.
Geological Context
Natrolite typically forms in the cavities and amygdules of basaltic volcanic rocks, as well as in some granitic pegmatites and hydrothermal veins. It is a product of low-temperature hydrothermal alteration.
