Home Page	Biology	Chemistry	Physics	Science Superstars	Inventions	Teachers	Stress
Homework Help	Zephyrus Training	About Us	Contact Us	Credits	Disclaimer	Privacy	Cookies

 

 

ROCKS AND MINERALS

 

Did you know that the hardness of rocks and minerals is measured on a scale called

MOHS' HARDNESS SCALE

 

 

This shows that the hardness of minerals ranges from 1 - 10.

The softest is shown with a hardness of 1 - the hardest is 10.

Your fingernail has a hardness of about 2.5 and a knife blade is about 5.5.

 

 

MOHS' HARDNESS SCALE

Hardness Scale	Mineral	Hardness Test
1.	Talc	Talc is the softest mineral and can be scratched by your fingernail.
2.	Gypsum
3.	Calcite	Calcite can be scratched with a copper coin.
4.	Fluorite	Fluorite can be scratched by a knife blade or window glass.
5.	Apatite
6.	Orthoclase feldspar	Feldspar scratches a knife blade or window glass.
7.	Quartz
8.	Topaze
9.	Corundum
10.	Diamond	Diamond is the hardest known mineral and scratches all known materials.