FAQ
| HARDNESS | MINERAL |
| 10. | Diamond |
| 9. | Sapphire, Ruby |
| 8.5 | Spinel |
| 8. | Topaz, Emerald, Aquamarine, Heliodor, Morganite |
| 7.5 | Tourmaline, Garnet |
| 7. | Amethyst, Citrine, Smoky Quartz, |
| 6.5 | Tanzanite, Kunzite |
| 6. | Opal, Labradorite, Moonstone |
| 5. | Apatite |
| 4. | Fluorite, Malachite |
| 3. | Calcite, Fuchsite, Pearl |
| 2. | Gypsum |
| 1. | Talc |