Hallmarks

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

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

Hallmarks are often confused with "trademarks" or "maker's marks". A hallmark is not the mark of a manufacturer to distinguish his products from other manufacturers' products: that 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.

Many nations require, as a prerequisite to official hallmarking, that the maker or sponsor itself marks upon the item a responsibility mark and a claim of fineness. Responsibility marks are also required in the U.S. if metal fineness is claimed, even though there is no official hallmarking scheme in that country. Nevertheless, in nations with an official hallmarking scheme, the hallmark is only applied after the item has been assayed to determine that its purity conforms not only to the standards set down by the law but also with the maker's claims as to metal content.

In some nations, such as the UK, the hallmark is made up of several elements, including: a mark denoting the type of metal, the maker/sponsor's mark and the year of the marking. In England, the year of marking commences on May 19, the Feast Day of Saint Dunstan, patron saint of gold- and silversmiths. In other nations, such as Poland, the hallmark is a single mark indicating metal and fineness, augmented by a responsibility mark (known as a sponsor's mark in the UK). Within a group of nations which are signatories to an international convention known as the Vienna Convention on the Control of the Fineness and the Hallmarking of Precious Metal Objects, additional, optional yet official, marks may also be struck by the assay office. These can ease import obligations among and between the signatory states. Signatory countries each have a single representative hallmark which would be struck next to the Convention mark which represents the metal and fineness.

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