Erythrite
Bou Azzer, Morocco

This specimen measures 8cm x 6cm


Erythrite     Co3(AsO4)2 .8H2O

Arsenates, a hydrous arsenate of cobalt and nickel

Color and Luster: Deep purple red to bluish pink; vitreous, pearly on cleavage plane; streak pale red to light pink

Hardness: 1.5-2.5

Cleavage: Perfect, one direction lengthwise

Fracture: flexible, sectile

Crystals: Monoclinic; crystals rare but occur in radiating groups or striated acicular and earthy crusts and in globular or reniform shapes with drusy surfaces

Photo by Mary Sutherland


Descriptions taken from
The Audubon Society Field Guide to North American Rocks and Minerals