Sterling zilver is mechanisch sterker, maar chemisch ("zuur zweet") wat zwakker als puur zilver, vandaar dat verzilveren (met >99.9% puur zilver) nut heeft als bescherming.
Zie onderstaande beschrijving (ging oorspronkelijk over bestek, maarja.....
): Sterling silver is a popular metal for jewelry, silverware and decorations. Sterling silver is an alloy of silver that consists of 92.5% pure silver and 7.5% of other metal, usually copper . Fine silver (99.9% pure) typically is too soft for practical objects. Alloying with copper maintains the silvery color of the metal, while increasing its strength. However, the copper is much more susceptible to oxidation and corrosion, so sterling silver tarnishes more easily than fine silver.