MOHS Scale of Hardness
Mohs Scale of Hardness
Hardness | Substance |
---|---|
2.5 | Amber, Ivory, Shell |
3-4 | Pearl |
5 | Glass |
5.5-5 | Lapis, Lazuli |
5-6 | Opal, Turquoise |
6-6.5 | Sodalite |
6-7 | Onyx, Peridot, Quartz |
7 | Agate, Amethyst, Citrine, Prasiolite |
7-7.5 | Garnet, Tourmaline |
7.5 | Zircone |
7.5-8 | Aquamarine, Emerald |
8 | Topaz |
8.5 | Alexandrite |
9 | Ruby, Sapphire |
10 | Diamond |
A hardness of 1 or 2 can be scratched with a fingernail, 3 to 4 scratched with a penny, 5-6 scratched with a knife blade, 6 scratched with a stepl file, 7 to 10 can scratch glass. |