Measured: Hardness is quoted on the Mohs scale from 1 to 10, a scratch ranking in which each material marks everything softer than itself and diamond alone reaches 10.
The basics
What to know about stone
What sits in the setting decides most of a piece's price and nearly all of its care. Listings run from mined diamond through cultured pearl to real faceted glass. Each material scratches, chips, stains and cleans differently, so identical designs behave differently in the hand.
Hardness is the working measure, given on the Mohs scale from 1 to 10. It ranks scratch resistance only: each material marks everything below it and nothing above. Household dust contains quartz at 7, which is why anything softer loses its polish just from being wiped. Toughness is separate, and diamond proves it by sitting at 10 while still chipping when struck on an edge.
Match hardness to how the piece will be worn. A ring takes many times the abuse of a pendant, so a stone below 7 belongs on the neck or the ear rather than the hand. Naming matters too: natural, created and simulated are three different claims, and careful sellers use them precisely.
