Lazulite

Lazulite is a blue, phosphate mineral containing magnesium, iron, and aluminium phosphate. It forms one endmember of a solid solution series with the darker iron rich scorzalite.

Lazulite crystallizes in the monoclinic system. Crystal habits include steep bipyramidal or wedge-shaped crystals. Lazulite has a Mohs hardness of 5.5 to 6 and a specific gravity of 3.0 to 3.1. It is infusible and insoluble.

It was first described in 1795 for deposits in Styria, Austria. Its name comes from the German lazurstein, for ‘blue stone’ or from the Arabic for heaven. It may confused with lazurite, lapis lazuli or azurite.