Diamond vs Quartz
| Property | Diamond | Quartz |
|---|---|---|
| Formula | C | SiO2 |
| Crystal System | Cubic (Isometric) | Trigonal |
| Mineral Class | 01 Native Elements | 09 Silicates |
| Mohs Hardness | 10.0 | 7.0 |
| Color | Colorless, yellow, brown, blue, green, pink | Colorless, white, purple, pink, brown, black |
| Luster | Adamantine | Vitreous |
| Streak | None | White |
| Transparency | Transparent | Transparent |
| Cleavage | Perfect octahedral {111} | None |
| Fracture | Conchoidal | Conchoidal |
Key Differences
- ◆ Diamond (hardness 10) is the hardest known mineral; quartz rates 7 on the Mohs scale.
- ◆ Diamond is pure carbon (C); quartz is silicon dioxide (SiO2).
- ◆ Diamond has an adamantine luster; quartz has a vitreous (glassy) luster.
- ◆ Diamond has perfect octahedral cleavage; quartz has no cleavage and fractures conchoidally.
- ◆ Diamond is far rarer and more expensive; quartz is the second most abundant mineral in Earth's crust.