HARDNESS

THE RESISTANCE OF A MATERIAL TO SCRATCHING AND WEAR. HARDNESS IS MEASURED USING THE MOH’S SCALE. THIS SCALE INDICATES THAT ONE SUBSTANCE CAN SCRATCH THE SUBSTANCE BELOW IT AND SCRATCH ITSELF. FOR EXAMPLE, A DIAMOND (10) WILL SCRATCH RUBY (9) AND ITS SELF, BUT NOT THE OTHER WAY AROUND, SO A DIAMOND IS HARDER.