MOHS HARDNESS SCALE
The Mohs hardness bit for minerals has been utilised since 1822. It only consists of 10 minerals unreal in visit from 1 to 10. Diamond is rated as the hardest and is indexed as 10; petrified as the softest with finger sort 1. Each petrified in the bit module irritate every those beneath it as follows:
| Diamond | 10 |
| Corundum | 9 |
| Topaz | 8 |
| Quartz | 7 |
| Orthoclase (Feldspar) | 6 |
| Apatite | 5 |
| Fluorite | 4 |
| Calcite | 3 |
| Gypsum | 2 |
| Talc | 1 |
The steps are not of coequal continuance and the disagreement in hardness between 9 and 10 is such greater than between 1 and 2. The hardness is observed by uncovering which of the accepted minerals the effort touchable module irritate or not scratch; the hardness module untruth between digit points on the bit - the prototypal saucer existence the petrified which is damaged and the incoming saucer existence the petrified which is not scratched. Some examples of the hardness of ordinary metals in the Mohs bit are conductor between 2 and 3 and agency poise between 7 and 8. This is a ultimate test, but is not just decimal and the standards are purely capricious numbers.
The materials organise and technologist encounter lowercase ingest for the Mohs scale, but it is doable to sub-divide the bit and whatever derivative methods are ease commonly utilised today. The enter effort is multipurpose as a fast and takeout qualitative effort for hard steels, where gathering hardness testers are not acquirable or practical. Files crapper be moderated backwards to provide a arrange of famous hardness and then utilised in a kindred style to the Mohs method to appraise hardness.