100 minerals and precious stones according to the degree of hardness

The Mohs hardness Scale is a practical system for comparing the hardness of minerals. It was proposed by the German mineralogist Friedrich Moos in 1812

Hardness is determined by the ability of one mineral to scratch another. The scale contains ten reference minerals with increasing hardness:

1. talcum powder

2. gypsum

3. calcite

4. Fluorite

5. appatite

6. Orthoclase (feldspar)

7. Quartz

8. Topaz

9. corundum

10. Diamond

The scale is not linear — the difference between neighboring levels can vary greatly. For example, the difference in hardness between diamond (10) and corundum (9) is significantly greater than that between corundum (9) and topaz (8)