The Mohs Scale of Mineral Hardness displays the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by geologist Friedrich Mohs. It lists ten minerals, ranging from Talc (Softest Known Mineral) at 1 to Diamond (Hardest Known Mineral) at 10.
Mohs Scale of Mineral Hardness is as follows:

1 - Talc
2 - Gypsum
3 - Calcite
4 - Fluorite
5 - Apatite
6 - Orthoclase Feldspar
7 - Quartz
8 - Topaz
9 - Corundum
10 - Diamond
by Some you'll never meet January 5, 2013
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