Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
orthorhombiccommonSilicates (Zeolite Group)
Natrolite
Na₂Al₂Si₃O₁₀·2H₂O
This specimen features a delicate, radiating cluster of acicular (needle-like) Natrolite crystals, which are predominantly white to colorless and exhibit a vitreous luster.
Natrolite Physical Properties
Mohs Hardness
5Crystal System
orthorhombicLuster
vitreousStreak Color
whiteCleavage
perfect on {110}Fracture
unevenSpecific Gravity
2.25Colors
white, colorlessTransparency
transparentType Locality
Cepei Alp (Cipit; Cipitbach; Tschapitbach; Tschipitbach), Castelrotto, Siusi Alp (Seis Alp), Gardena Valley (Gröden Valley), Province of Bolzano-BozenMineral Group
Silicates (Zeolite Group)Uses
collector, industrial (adsorbent, catalyst)Associated Minerals
stilbite, heulandite, apophyllite, calcite, quartzRarity
commonGeological Context
Natrolite commonly forms in the cavities and vugs of basaltic and other volcanic rocks, as well as in some metamorphic rocks, through low-temperature hydrothermal alteration processes.
