A Hallmark is a mark or a series of marks that are stamped onto certain metals to certify their preciousness and purity.


We have read all the hallmarks on our jewellery as accurately as possible. Please note due to the age of some of our pieces often the hallmarks have become worn and can be difficult to see.

If you have any questions regarding the hallmarks on any of our pieces please get in touch info@pilondon.co.uk



The PI London Glossary

Hallmarks are something that we find fascinating, they are like a secret coded message.

In order to help you decipher the code we hope our hallmark glossary helps. Hopefully you will be able to start decoding hallmarks on other pieces you see, we’d love to hear how you get on. 



There are 4 assay offices still in use in the UK:

Birmingham (Anchor symbol), Sheffield (Rose), London, (Leopard)Edinburgh (Castle)

London 1678 - Present

Birmingham 1773 - Present

Sheffield 1773 - Present

Edinburgh 1705 - Present

Chester - closed in 1962

Exeter - closed in 1883

Glasgow - closed in 1964

Newcastle upon Tyne - closed in 1884



If your gold is inscribed with the ‘375’ hallmark, it means that it is 37.5 per cent solid gold, 9 carat or 9ct gold for short. 

The ‘500’ hallmark, means that it is 50 per cent solid gold, or 12ct.

The list goes on, ‘585’ is 14ct, ‘625’ is 15ct, ‘750’ means 18ct, ‘916’ is for 22ct and ‘999’ which is the purest gold you can get is 24 ct.

The age of a piece of jewellery is indicated by letters of the alphabet.

The alphabetic sequences are also differentiated by changes in typeface, punch shape, and changes from upper to lower case characters.

Here at PI London all of our pieces are 9ct (375) gold or more.

We will never have plated or gold filled pieces as we believe jewellery should last a lifetime.

If you have any questions about hallmarks please do get in touch, you can email us at info@pilondon.co.uk