Devised in 1822 by German mineralogist Friedrich Mohs, the Mohs scale consists of 10 minerals arranged in order from 1 (softest) to 10 (hardest). Each mineral in the scale will scratch all those below it. The Mohs hardness scale is commonly used, because the minerals are easily obtained.
| 10 | diamond |  |
|
| 9 | corundum | ||
| 8 | topaz | ||
| steel file | 7 | quartz | |
| pocket
knife, glass = 5.5 |
6 | orthoclase, feldspar |
|
| 5 | apatite | ||
| 4 | flourite | ||
| copper
coin = 3 fingernail = 2.5 |
3 | calcite | |
| 2 | gypsum, selenite |
||
| 1 | talc |
Photos by Jeff Thomas, November 29, 2004.
Minerals purchased from DJ
Minerals.