A sterling silver

Sterling silver

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

 object that is to be sold commercially is, in most countries, stamped with one or more silver hallmarks indicating the purity of the silver, the mark of the manufacturer or silversmith, and other (optional) markings to indicate date of manufacture and additional information about the piece. In some countries, the testing of silver objects and marking of purity is controlled by a national assayer's office

Assay office

Assay offices are institutions set up to assay precious metals, in order to protect consumers. Upon successful completion of an assay, Assay offices are institutions set up to assay (test the purity of) precious metals, in order to protect consumers. Upon successful completion of an assay, Assay...

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Hallmarks are applied with a hammer and punch, a process that leaves sharp edges and spurs of metal.