Natrolite

Introduction: Natrium is the Latin word for sodium and belongs to the zeolite group of minerals. Stunning large natrolite crystals, some up to 10cm long, were discovered in the construction of the Hardap Dam near Mariental.

Distribution: Hardap Dam and in cavities in the Aris phonolites south of Windhoek.

Composition: Silicate

Crystal system: Orthorhombic

Lustre: Pearly, Vitreous

Streak: White

Hardness: 5-5.5