Erythrine

Erythrite is a rare mineral from the arsenate group, composed of hydrated cobalt arsenate (Co₃(AsO₄)₂·8H₂O). It is easily recognizable by its spectacular raspberry pink to purplish red color, due to the presence of cobalt.

It generally forms fine acicular crystals or crust aggregates in the oxidation zones of cobalt and arsenic deposits. Specimens from Morocco, particularly Bou Azzer, are among the best known for their magnificent pink crystals associated with dolomite, calcite, or malachite.