Properties
| Category | Phosphate mineral |
|---|---|
| Formula | (Mg,Fe2+)Al2(PO4)2(OH)2 |
| Crystal system | Monoclinic |
| Color | Azure, sky blue, bluish white, yellow-green, blue-green, rarely green |
| Crystal habit | Tabular, acute to stubby bipyramidal crystals; granular, massive |
| Cleavage | Poor to good on {110}, indistinct on {101} |
| Fracture | Uneven, splintery |
| Tenacity | Brittle |
| Mohs scale hardness | 5.5–6.0 |
| Luster | Vitreous |
| Streak | White |
| Diaphaneity | Transparent to translucent to nearly opaque |
| Specific gravity | 3.122–3.240 |
From the Wikipedia article
Lazulite or Azure spar is a transparent to semi-opaque, blue mineral that is a phosphate of magnesium, iron, and aluminium, with the chemical formula (Mg,Fe2+)Al2(PO4)2(OH)2. Lazulite forms one endmember of a solid solution series with the darker, iron-rich scorzalite.
Source
Source record: crystal-compendium/lazulite/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Lazulite — revision id 1310302230. Text and properties from Wikipedia, licensed CC BY-SA 4.0.