Hallmark

A hallmark is an official mark or series of marks struck on items made of precious metals—platinum, gold, silver and in some nations, palladium. In a more general sense, the term hallmark can also be used to refer to any distinguishing characteristic.

General overview

Historically, hallmarks were applied by a trusted party: the 'guardians of the craft' or nowadays by an assay office. Hallmarks are a guarantee of certain purity or fineness of the metal as determined by formal metal (assay) testing.

Distinguishment

Hallmarks are often confused with "trademarks" or "maker's mark". Hallmarks are not the mark of a manufacturer to distinguish his products from other manufacturers’ products, which is the function of trademarks or makers' marks. To be a true hallmark, it must be the guarantee of an independent body or authority that the contents are as marked. Thus, a stamp of '925' by itself is not, strictly speaking, a hallmark, but is rather an unattested fineness mark.

Prerequisites to hallmarking