INTRINSIC CHARACTERISTICS

A fourth point is that Mohs was a mineralogist and interested ir the hardness of all minerals, not only gems. For that reason, the scale contains some minerals that are not used as gems. In addition, because the scientific names are used, even the names of some of the minerals used as gems may be unfamiliar. Thus, examples of gems familiar to consumers are given in parentheses after the species name, when applicable.

MOHS SCALE
1. Talc
2.Gypsum
3.Calcite
4.Fluorite
5.Apatite (one kind of cat's-eye is apatite)
6.Feldspar (moonstone is the most familiar feldspar)
7. Quartz (examples are amethyst, bloodstone, tigereye agate, and other forms of quartz)
8. Topaz
9. Corundum (rubies and sapphires are corundum)
10.Diamond

Reading this table and the explanation preceding it, you note that diamonds will scratch all other minerals. A sapphire, on the other hand, will be scratched by a diamond but will scratch all below it on the scale, and so on.

Scratchability can be defined in another way that may be more For example, the hardness of a fingernail is about 2'/2. That you can scratch talc (1)-it would be like scratching : gypsum (2) with your own fingernail. You would need a, ever, to scratch calcite.