Hardness Scale

(these values can vary!)

 

Mineral (or other item)

Mohs Scale

Absolute Hardness (not used in this class)

 

 

 

 

 

 

 

Talc

1

1

 

 

Piece of chalk

1

 

 

 

 

 

 

 

 

Gypsum

2

2

 

 

Plaster of Paris

2

 

 

 

Fingernail

2.5

 

 

 

Pure gold, silver, aluminum

2.5 - 3

 

 

 

 

 

 

 

 

Calcite

3

9

 

 

Bronze

3

 

 

 

Copper (penny)

3 - 3.5

 

 

 

 

 

 

 

 

Fluorite

4

21

 

 

Iron nail

4 4.5

 

 

 

Platinum

4 4.5

 

 

 

Iron

4 - 5

 

 

 

 

 

 

 

 

Apatite

5

48

 

 

Knife

5.5

 

 

 

Masonry nail

5.5

 

 

 

 

 

 

 

 

Orthoclase

6

72

 

 

Titanium

6

 

 

 

Iron pyrite

6.5

 

 

 

File

6.5

 

 

 

Streak plate

6.5

 

 

 

Glass, Vitreous pure silica

6 - 7

 

 

 

 

 

 

 

 

Quartz

7

100

 

 

Garnet

7 7.5

 

 

 

Hardened steel

7 - 8

 

 

 

 

 

 

 

 

Beryl - Topaz

8

200

 

 

 

 

 

 

 

 

 

 

 

 

Corundum

9

400

 

 

carborundum

9 9.5

 

 

 

 

 

 

 

 

Diamond

10

1,500