Lapis lazuli
Lapis lazuli /ˈlæpɪs ləˈzuːliː/ or /-ˈlæʒuːlaɪ/ (whiles abbreviate tae lapis) is a deep blae semi-precious stane that haes been prized syne antiquity for its intense colour.
| Lapis lazuli | |
|---|---|
 Lapis lazuli frae Afghanistan in its naitural state | |
| General | |
| Category | Rock |
| Formula (repeatin unit) | mixtur o minerals wi lazurite as the main constituent. |
| Creestal seestem | None, as lapis is a rock. Lazurite, the main constituent, frequently occurs as dodecahedra |
| Identification | |
| Colour | Medium Blue, mottled wi white calcite an brassy pyrite |
| Creestal habit | Compact, massive |
| Fractur | Uneven-Conchoidal |
| Mohs scale haurdness | 5–5.5 |
| Skinkle | dull |
| Streak | light blue |
| Speceefic gravity | 2.7–2.9 |
| Refractive index | 1.5 |
| Ither chairacteristics | The variations in composeetion cause a wide variation in the abuin values. |