A guide to resources for identifying hallmarks and understanding the process of assaying



A hallmark is a stamp applied to an article of precious metal (gold, silver, platinum and palladium) after testing by an official independent assay office, which denotes the fineness of quality.

Hallmarking dates back to the craft guilds in the 1300s and is the oldest form of consumer protection which in view of the historically high price of precious metal and with globalisation, is more important than ever.

Hallmarking is supported by legislation in both United Kingdom and Ireland and these countries have the most stringent requirements for hallmarking.


Precious metals are too soft to be used unless alloyed with other metals.  Therefore all precious metal articles must be “assayed” or tested for purity before being offered for sale in the United Kingdom or Ireland.

Assay office

Assay offices test the purity of precious metals, in order to protect consumers. Articles less than a prescribed weight may be exempt.

Assay office mark

Also known as the 'town mark', this identifies the office at which the assaying and marking were done.      

  • Birmingham uses an anchorAssay Office marks
  • Edinburgh uses a three tower castle
  • London uses the leopard's head    
  • Sheffield uses the York rose
  • Dublin uses the figure of Hibernia

Maker’s or sponsor’s mark

This mark consists of the initials of the maker surrounded by a shield.  An assay office will only accept a design for this mark if it is totally distinct from any other mark registered with that office.

Metal and fineness [purity] mark - Standard mark

This is a traditional mark indicating the purity of the metal. It will either be represented by a numerical value, or a symbol.

Numerical value

Sterling silver                     925 parts per thousand

Britannia silver                   958 parts per thousand

22 carat gold                      916  parts per thousand 

18 carat gold                      750  parts per thousand

14 carat gold                      585 parts per thousand

9 carat gold                        375 parts per thousand

Traditional fineness symbols

  • sterling silver lion passantHallmark symbols
  • sterling silver Scotland  lion rampant
  • Britannia silver
  • palladium Pallas Athena (helmet)
  • gold crown
  • platinum orb

Date letter

The date letter shows the year that assaying was carried out. Prior to 1975 the date letter varied for every office, after that it was uniform throughout the United Kingdom. 

Since 1999, the date letter has been voluntary. Most silver and goldsmiths making bespoke pieces will still opt to use the date letter, however for mass produced silver items it saves the importers money to leave it off.


Silver dishes

Pair of sterling silver sweetmeat dishes made in 1780 by Richard Morton & Co

Pair of sterling silver sweetmeat dishes made in 1780 by Richard Morton & Co [Note the hallmarks near the bottom of the upper image] H2008.11/461