Overview
Sterling silver is an alloy composed by weight of 92.5% silver and 7.5% other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925.
Fine silver, which is 99.9% pure silver, is relatively soft, so silver is usually alloyed with copper to increase its hardness and strength. Sterling silver is prone to tarnishing, and elements other than copper can be used in alloys to reduce tarnishing, as well as casting porosity and firescale. Such elements include germanium, zinc, platinum, silicon, and boron. Recent examples of these alloys include argentium, sterlium and silvadium.
Etymology
One of the earliest attestations of the term is in Old French form , in a charter of the abbey of Les Préaux, dating to either 1085 or 1104. The English chronicler Orderic Vitalis (1075 – 1142) uses the Latin forms and . The word in origin refers to the newly introduced Norman silver penny.
According to the Oxford English Dictionary, the most plausible etymology is a derivation from a late Old English (with, or like, a 'little star'), as some early Norman pennies were imprinted with a small star.
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