Cordierite

Introduction: Cordierite occurs in granites and various metamorphic rocks, mainly in alluvial deposits due to its hardness. This mineral is named after a French geologist, Pierre Louis Antoine Cordier. Usually blue, it can also be violet, grey, brown, yellow or green.

Distribution: Between Walvis Bay and Rooibank north of Zebra Mountain and many other central and coastal locations including between Henties Bay and Swakopmund.

Composition: Silicate

Crystal system: Orthorhombic

Lustre: Vitreous

Streak: White

Hardness: 7-7.5