• Mohs' scale of mineral hardness

 

Ranking

Mineral

Natural form

Form of usage

Softest

1

Talc

   
 

2

Gypsum

   
 

3

Calcite

 
 

4

Fluorite

   
 

5

Apatite

   
 

6

Feldspar

   
 

7

Quartz

   
 

8

Topaz

   
 

9

Corundum

   

Hardest

10

Diamond

   

Diagrams | Earthguide