Hardness of Common Minerals
The hardness of minerals refers to their ability to resist scratching or abrasion. It is measured on the Mohs scale, which assigns a hardness value from 1 (softest) to 10 (hardest). A mineral with a higher Mohs hardness can scratch a mineral with a lower hardness. For example, diamond, with a hardness of 10, can scratch any other mineral, while talc, with a hardness of 1, can be easily scratched by most minerals.
The following table provides a comprehensive list of Mohs hardness values for different minerals at room temperature (approximately 20°C or 68°F).
| Actinolite | 5.5 |
| Albite | 6.3 |
| Almandine | 6.8 |
| Anatase | 5.8 |
| Andalusite | 7.5 |
| Andesine | 6.3 |
| Anhydrite | 3.5 |
| Apatite | 5 |
| Apophyllite | 4.8 |
| Aragonite | 3.5 |
| Arsenopyrite | 5.8 |
| Augite | 6 |
| Azurite | 3.8 |
| Barite | 3.3 |
| Benitoite | 6.3 |
| Beryl | 7.8 |
| Biotite | 2.8 |
| Borax | 2.3 |
| Bornite | 3 |
| Brucite | 2.5 |
| Calcite | 3 |
| Carbon (diamond) | 10 |
| Cassiterite | 6.5 |
| Chalcopyrite | 3.8 |
| Chlorite | 2.5 |
| Chromite | 5.5 |
| Chrysocolla | 2 |
| Cinnabar | 2.3 |
| Cordierite | 7 |
| Corundum | 9 |
| Covellite | 1.8 |
| Cuprite | 3.8 |
| Danburite | 7 |
| Diaspore | 6.8 |
| Diopside | 6 |
| Dioptase | 5 |
| Dolomite | 3.5 |
| Enstatite | 5.5 |
| Epidote | 6 |
| Fluorite | 4 |
| Galena | 2.5 |
| Goethite | 5.3 |
| Gypsum | 2 |
| Halite | 2 |
| Hematite | 6 |
| Hemimorphite | 5 |
| Hornblende | 5.5 |
| Ilmenite | 5.5 |
| Jadeite | 6 |
| Kaolinite | 2.3 |
| Kyanite | 6.3 |
| Lepidolite | 3.3 |
| Magnesite | 4 |
| Magnetite | 6 |
| Malachite | 3.8 |
| Marcasite | 6.3 |
| Molybdenite | 1.3 |
| Montmorillonite | 1.5 |
| Muscovite | 2.8 |
| Nepheline | 5.8 |
| Olivine | 6.8 |
| Opal | 5 |
| Orthoclase | 6 |
| Petalite | 6.5 |
| Phenakite | 7.5 |
| Prehnite | 6.3 |
| Psilomelane | 5.5 |
| Pyrite | 6.3 |
| Pyrolusite | 6.3 |
| Pyrope | 6.8 |
| Pyrrhotite | 4 |
| Quartz (α) | 7 |
| Realgar | 1.8 |
| Rutile | 6.2 |
| Scapolite | 5.5 |
| Scolecite | 5 |
| Serpentine | 3 |
| Siderite | 4.3 |
| Sillimanite | 7 |
| Smithsonite | 4.3 |
| Sodalite | 5.8 |
| Spessartite | 6.8 |
| Sphalerite | 3.8 |
| Sphene | 5 |
| Spinel | 7.8 |
| Staurolite | 7.5 |
| Stibnite | 2 |
| Stilbite | 3.8 |
| Struvite | 2 |
| Sulfur (orthorhombic) | 2 |
| Talc | 1 |
| Topaz | 8 |
| Tourmaline | 7 |
| Vanadinite | 2.9 |
| Vermiculite | 1.5 |
| Vesuvianite | 6.5 |
| Wollastonite | 4.8 |
| Wulfenite | 2.9 |
| Wurtzite | 3.8 |
| Zircon | 7.5 |
| Zoisite | 6 |
Related Tables
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017.