Mohs Scale of Mineral Hardness
The Mohs scale was devised by Frederich Mohs in 1812. You use the scale by testing your unknown mineral against a known standard. Which ever one scratches the other is harder, and if both scratch each other they are the same hardness.
Diamond
10
Corundum
9
Ruby
9
Sapphire
9
Alexandrite
8.5
Chrysoberyl
8.5
Rhodozite
8
Spinel
8
Taaffeite
8
Topaz
8
Yag
8
Aquamarine
7.5 – 8
Beryl
7.5 – 8
Emerald
7.5 – 8
Gahnite
7.5 – 8
Painite
7.5 – 8
Phenacite
7.5 – 8
Almandine
7.5
Andalusite
7.5
Euclase
7.5
Hambergite
7.5
Uvarovite
7.5
Ceramic Streak Plate
7.5
Andradite
7 – 7.5
Cordierite
7 – 7.5
Danburite
7 – 7.5
Garnet
7 – 7.5
Iolite
7 – 7.5
Rhodolite
7 – 7.5
Staurolite
7 – 7.5
Tourmaline
7 – 7.5
Amethyst
7
Citrine
7
Dumortierite
7
Prasiolite
7
Rock-Crystal
7
Quartz (Smoky, Rose)
7
Tigers Eye
7
Zircon
6.5 – 7.5
Agate
6.5 – 7
Axinite
6.5 – 7
Chalcedony
6.5 – 7
Chloromelanite
6.5 – 7
Chrysoprase
6.5 – 7
Demantoid
6.5 – 7
Petrified Wood
6.5 – 7
Heliotrope
6.5 – 7
Jadeite
6.5 – 7
Jasper
6.5 – 7
Kornerupine
6.5 – 7
Peridot
6.5 – 7
Sard
6.5 – 7
Tanzanite
6.5 – 7
Ziosite
6.5 – 7
Idocrase
6.5
Saussurite
6.5
Sinhalite
6.5
Smaragdite
6.5
Steel File
6.5
Sillimanite
6 – 7.5
Epidote
6 – 7
Cassiterite
6 – 7
Epidote
6 – 7
Hiddenite
6 – 7
Kunzite
6 – 7
Unakite
6 – 7
Amazonite
6 – 6.5
Aventurine
6 – 6.5
Feldspar
6 – 6.5
Benitoite
6 – 6.5
Ekanite
6 – 6.5
Labradorite
6 – 6.5
Moonstone
6 – 6.5
Nephrite-Jade
6 – 6.5
Petalite
6 – 6.5
Prehnite
6 – 6.5
Pyrite
6 – 6.5
Rutile
6 – 6.5
Strontium
6 – 6.5
Titanate
6 – 6.5
Amblygonite
6
Bytownite
6
Orthoclase
6
Sanidine
6
Thulite
6
Tugtupite
6
Hematite
5.5 – 6.5
Opal
5.5 – 6.5
Rhodonite
5.5 – 6.5
Tremolite
5.5 – 6.5
Actinolite
5.5 – 6.5
Anatase
5.5 – 6.5
Beryllonite
5.5 – 6
Elaeolite
5.5 – 6
Hauynite
5.5 – 6
Periclase
5.5 – 6
Psilomelane
5.5 – 6
Sodalite
5.5 – 6
Brazilianite
5.5
Chromite
5.5
Enstatite
5.5
Goldstone
5.5
Leucite
5.5
Moldavite
5.5
Natrolite
5.5
Willemite
5.5
Window Glass
5.5
Scapolite
5 – 6.5
Cancrinite
5 – 6
Chlorastrolite
5 – 6
Diopside
5 – 6
Hypersthene
5 – 6
Limenite
5 – 6
Lapis Lazuli
5 – 6
Lazulite
5 – 6
Tantalite
5 – 6
Turquoise
5 – 6
Datolite
5 – 5.5
Obsidian
5 – 5.5
Sphene
5 – 5.5
Thomasonite
5 – 5.5
Steel Knife Blade
5.5
Apatite
5
Augelite
5
Dioptase
5
Hemimorphite
5
Smithsonite
5
Wardite
5
Kyanite
4.5 – 7
Apophyllite
4.5 – 5
Scheelite
4.5 – 5
Zincite
4.5 – 5
Colemanite
4.5
Kurnakovite
4.5
Purpurite
4.5
Wire Nail
4.5
Variscite
4.5
Flourite
4
Barytocalcite
4
Magnesite
4
Rhodochrosite
4
Dolomite
3.5 – 4.5
Chalybite
3.5 – 4.5