Lazulite - MgAl₂(PO₄)₂(OH)₂

Habit: Azure blue, sky blue, bluish white, yellow green or blue green; rarely green. Crystals acute pyramidal; also tabular, massive compact or granular. Vitreous luster; transparent to translucent, and may be nearly opaque. White streak.

Environment: Found in aluminous high-grade metamorphic rocks with quartz as disseminated grains, in quartz veins or dikes in these rocks, or in granitic pegmatites.

Etymology: From the German lazurstein, meaning "blue stone."