There are also different types. According to the Mohs scale for the hardness of materials applies approximately:
Designation | Mohs hardness |
---|---|
Diamond | 10 |
CBN | 9-10 |
Silicon carbide (corundum) | 9.6 |
Aluminum oxide | 9-9.5 |
Silicon dioxide | 7 |
A stone with a higher Mohs hardness than another can scratch the other, but not vice versa. The important Materials: