thumb|alt=Open wooden box with ten compartments, each containing a numbered mineral specimen.|Mohs hardness kit, containing one specimen of each mineral on the ten-point hardness scale
The Mohs scale ( ) of mineral hardness is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of minerals through the ability of harder material to scratch softer material.
The scale was introduced in 1812 by the German geologist and mineralogist Friedrich Mohs, in his book ();