Natrolite is a common and popular member of the Zeolite group, and is known for its needle-like crystal habits. It is closely related to Mesolite and Scolecite and can appear very similar to them. Mesolite’s fiber-like crystals are typically the thinnest of the three, while Scolecite’s larger crystals tend to be more substantial and durable. Its color is white, off-white and colorless with a vitreous to silky luster. This impressive mineral is associated with other numerous quality and contrasting minerals, including Calcite, Thomsonite, Prehnite, Apophyllite and other Zeolites.
The crystal system for Natrolite is orthorhombic, most often forming dense acicular, fibrous and radial groupings, and well as in spiky rounded aggregates, dense tufts and globular; all habits often form in cavities and vugs (this particular form is very aesthetic and provides natural protection for the mineral crystals).
Quality Natrolite specimens are found in limited localities, including Australia, Canada, Czech Republic, France, India, Italy and the USA (New Jersey).