General

Mohs Scale of Mineral Hardness

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