Mohs Scale of Hardness
October 31, 2017
Updated November 8, 2026
The Mohs scale compares a mineral’s resistance to scratching. It runs from talc at 1 to diamond at 10. The steps are relative: a gemstone rated 10 is not simply ten times harder than one rated 1.
Hardness is not toughness
Scratch resistance does not tell the whole story. Toughness describes resistance to chipping or breaking, while stability concerns how a gem responds to heat, light, or chemicals. Even a diamond can chip from an impact.
What it means for your jewelry
Consider the gemstone, its setting, and how often the piece will be worn. Softer or more fragile gems may benefit from protective designs and extra care. Store pieces separately so harder stones do not scratch softer ones, and ask us about care for your particular piece.
Reference: GIA’s guide to gemstone durability and engagement rings.