Silver hallmarks

A silver 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.

Hallmarks are applied with a hammer and punch, a process that leaves sharp edges and spurs of metal. Therefore, hallmarking is generally done before the piece goes for its final polishing.

The hallmark for sterling silver varies from nation to nation, often using distinctive historic symbols, although Dutch and UK Assay offices no longer strike their traditional hallmarks exclusively in their own territories and undertake assay in other countries using marks that are the same as those used domestically.

One of the most highly structured hallmarking systems in the world is that of the United Kingdom, (Scotland, England, Wales and Northern Ireland), and Ireland. These five nations have, historically, provided a wealth of information about a piece through their series of applied punches. It should be noted that since 2015 visually identical UK Hallmarks are being struck in India and Italy by sub-offices of Birmingham & Sheffield Assay Offices respectively:

The series of hallmarks described above are still in use in today.

However, there are two silver hallmarks that have been discontinued:

The French assay mark for sterling silver is the head of the goddess Minerva. In fact, the French standard for sterling silver is higher than that of other nations, requiring a silver content of 950 parts per thousand, or 95% silver. Silver items with a slightly lower grade of silver, 800 parts per thousand, are marked with the head of Minerva, next to which is a "2".

French silver made for export carries an assay mark in the shape of the head of Mercury, along with a number to indicate the millesimal fineness: "1" for .920, "2" for .840 and "3" for .750.

French silver also is punched with the mark of the maker.

In the early United States, no national assaying system was adopted, although the city of Baltimore did maintain its own assay office between 1814 and 1830. Prior to the general adoption of sterling silver as the standard of purity in 1868, silver was generally obtained from the melting of coins. Since these could vary considerably in purity, from around .750 millesimal fineness to around .900, silver known as "coin silver" varies in purity. Silver at that time was sometimes marked "COIN" or "PURE COIN", but can also be without a standard mark altogether. After the adoption of the sterling standard, pieces were marked with "STERLING", the number "925" or the notation "925/1000".

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Wikipedia