UK Hallmarking Explained

Thursday, 23 February 2017  |  Victoria

What is a UK hallmark?

Silver, palladium, gold and platinum ('precious metals') are normally alloyed with other metals in order to improve their strength, durability and colour etc. A hallmark is a legal requirement which guarantees the purity (fineness) of the precious metal. It consists of three symbols:

  • the maker's or sponsors mark: this is a unique mark and the maker/sponsor must be registered with an assay office.
  • metal purity mark: this indicates that the metal content of the item is not less than the fineness indicated.
  • assay office mark:  this indicates the Assay Office at which the item was tested and marked (London, Edinburgh, Birmingham and Sheffield each have their own mark)
  • (optional) a year mark: a letter indicating the year in which the item was hallmarked

A hallmark is NOT a single fineness mark on an article eg a ring with a single 925 stamp - anyone can stamp these marks on any article and they do not indicate an officially recognised guarantee of the fineness of the metal.

Other countries will have different rules and not all countries have official hallmarking schemes, eg USA.

Which articles need to be hallmarked?

Any item sold in the UK (regardless of where it was manufactured) described as being made of gold, silver, palladium or platinum (subject to certain exemptions) needs to be hallmarked. Items below the following weights are exempt:

  • Silver: 7.78 grams
  • Palladium: 1 gram
  • Gold 1 gram
  • Platinum: 0.5 grams

A pre-1950 item may be described as a precious without a hallmark if the seller can prove it is of minimum fineness and was made before 1950.

Items made of gold plated base metals cannot be hallmarked (including gold filled items). A gold plated silver item can only be given the silver hallmark.

Further Information

Hallmarking Act 1973
British Hallmarking Council
Birmingham Assay Office
Edinburgh Assay Office
London Assay Office
Sheffield Assay Office