Corundum vs Turquoise
| Property | Corundum | Turquoise |
|---|---|---|
| Formula | Al2O3 | CuAl6(PO4)4(OH)8 · 4H2O |
| Crystal System | Trigonal | Triclinic |
| Mineral Class | 04 Oxides and Hydroxides | 08 Phosphates, Arsenates, and Vanadates |
| Mohs Hardness | 9.0 | 5.0-6.0 |
| Color | Red (ruby), blue (sapphire), various colors | Sky blue, blue-green, green |
| Luster | Adamantine | Waxy |
| Streak | Colorless | White to pale green |
| Transparency | Transparent | Translucent |
| Cleavage | None | None |
| Fracture | Conchoidal to uneven | Conchoidal |