HOW HARDNESS IS MEASURED
This scale helps scientists identify and categorise minerals
WORDS AILSA HARVEY
Mohs developed his interest in minerals by working in a mine
The Mohs hardness scale is a simple but effective ten-point scale that ranks minerals according to their hardness. It was devised by German mineralogist Friedrich Mohs in 1822 and places the softest minerals down the bottom at 1.0, while 10.0 indicates the hardest minerals, like diamond. Mohs gave ten minerals of increasing hardness arbitrary values in order to create a template for testing all other minerals.