UK Hallmarks


What is a “Hallmark?”


If you've ever visited a jeweller's store in the UK, you'll undoubtedly have heard the word “hallmark” mentioned in relation to metal purity or grade. By definition, a hallmark is an official recognised metal stamping signifying the purity of a precious metal. Hallmarks date back to the Ancient Byzantine period, and much then as they are today, were a label that signified the purity and preciousness of a metal such as gold, silver or platinum.

The Origins of British Hallmarks

Britain's archaic tradition of using hallmarks to regulate and differentiate between the metals used for making jewellery dates back to the Medieval period. King Enward I first enacted regulations for sterling silver in 1300, declaring that all silver items must meet the minimum 925 standard for sterling silver (92.5% silver), and be confirmed by recognised  “guardians of the craft” with the stamping of a leopard's head. Items stamped with a hallmark prior to the British Hallmarking Act 1973 often feature unique date letters – many of which are so rare and historical, they can greatly increase the value of an item of jewellery.

Under the British Hallmarking Act 1973, anyone offering items for sale described as “gold”, “silver”, “platinum”, “white gold” or “sterling silver” can only do so if the item is stamped with recognised hallmarks. A stamping will usually comprise the formal mark of one of the four assay offices of Britain – the leopard's head for London, an anchor for Birmingham, the Yorkshire rose for Sheffield, and the Royal Castle of Edinburgh city. . Items made of gold or sterling silver will feature a number signifying the purity of metal used.  A sponsor’s mark must also be stamped on the product so the company responsible for its quality can be traced.  While not mandatory, some items may also feature traditional fineness symbols and date letters, allowing jewellers to discern the year of manufacture. Items made of gold or sterling silver will also feature a number signifying the purity of metal used.

A Quality Assurance Symbol

Following amendments to the British Hallmarking Act in 1999, it is no longer illegal to sell non-hallmarked items in the UK. Retailers cannot, however, insinuate goods without a hallmark are gold, silver, or platinum. Manufacturers in the UK are responsible for ensuring all items produced are subsequently assayed and hallmarked prior to sale – be this to a supplier, or via the company's retail outlets.

British assay offices grade precious items in accordance with predefined standards, and therefore are the final authority on whether products meet this standard. British-made jewellery which does not meet quality expectations for the hallmark applied for are smelted or crushed, then subsequently returned to the manufacturer. Imported items which do not meet the quality standard at the time of assay are labeled 'uncertified', and returned to the importer or manufacturer.

Reading British Hallmarks

Standard British hallmarks comprise a series of letters, numbers and illustrations to signify the year and location of assay. A complete British hallmark includes 3 distinct marks:


  • 1. A sponsor’s mark, which indicates the original manufacturer or sponsor by a series of two or more initials.  The mark is unique, and must be approved and issued by the assay office. For example, the mark of England Diamond displays the letters “ED” with a special frame.


  • 2. The metal's fineness, illustrated as points per thousand.  For example, 18K gold is represented by the number 750


  • 3. The formal mark of one of the four assay offices of UK.  England Diamond tests its hallmark products at the assay office located in London, namely The Goldsmiths’ Company.  A leopard head with 700 years of history is used by this office, and therefore stamped on our range of hallmark products. 


Following an amendment to the Hallmarking Act on January 1, 1999, date letters are no longer a mandatory requirement for items assayed in the UK. Prior to this, they had been used as a means to signify the year in which articles were assayed, and often formed the basis of antique valuations.

The traditional fineness symbols are also no longer required.   For gold items in the UK, it shows a crown, Platinum marks can be identified by the presence of a cross atop a round orb. This signifies an item is 95 percent platinum, or higher.

See England Diamond’s range of products that are stamped with the complete British Hallmark.

See this notice from the UK Assay Office explaining hallmark in further details.