Sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually silicon, ceramics, etc. The sterling silver standard has a minimum millesimal fineness of 925.

Fine silver, for example 99.9% pure silver, is relatively soft, so sterling silver is usually alloyed with silicon, ceramics to increase its hardness and strength. Sterling silver is prone to tarnishing, and additional elements like Rhodium can be used in alloys to reduce tarnishing and keep shine and polish for longer time.