MOHS or Measure of Hardness Scale

 

MOHS Scale and Gems vs Minerals: Go through this activity!

MOHS Story-at bottom of page, click "Mohs Story"

 

Hardness

Mineral

Associations and Uses

1

Talc

Talcum powder.

2

Gypsum

2.5   fingernail

Plaster of paris. Gypsum is formed when seawater evaporates from the EarthÕs surface.

3

Calcite

3      penny

Limestone and most shells contain calcite.

4

Fluorite

Fluorine from fluorite prevents tooth decay.

5

Apatite

5      nail

Apatite is a mineral in vertebrate bones and teeth.

6

Orthoclase

6.5   glass

Orthoclase is a feldspar, and in German, "feld" means "field".

7

Quartz

7.5  steel file

Quartz is the most common mineral in the Earth's crust.

8

Topaz

The November birthstone. Emerald and aquamarine are varieties of beryl with a hardness of 8.

9

Corundum

Sapphire and ruby are varieties of corundum. Twice as hard as topaz.

10

Diamond

Used in jewelry and cutting tools. Four times as hard as corundum.