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Blue John Gallery - British Hallmark Approved Retailer



As a British Hallmark Approved Retailer, wherever you see products carrying the ‘Approved Product’ badge, this is provides all customers a guarantee they are purchasing the correct purity of precious metals and are able to shop with confidence, and peace of mind.


Where does hallmarking originate?
The word hallmark originates from the fifteenth century when London craftsmen were first required to bring their artifacts to Goldsmiths’ Hall for assaying and marking – an early form of consumer protection. Seven hundred years later Goldsmith’s Company (London) Assay Office, along with the other Assay Offices of the UK continue the tradition of guaranteeing the level of precious metal content in line with UK law.

What are the hallmarking standards today?
In the UK, all jewellery that is sold as having been made with gold, silver, platinum or palladium, must be hallmarked according to the Hallmarking Act 1973. Should a metal object weigh under a certain number of grams, they are exempt from the hallmarking law. Small jewellery items such as stud earrings or pendants may fall into this category and do not have to be hallmarked if their weight falls under:

1 gram for gold
0.5 gram for platinum & palladium
7.78 grams for silver

Who provides the hallmarking service?
All testing must be done by an Assay Office. There are 4 offices based in the UK – London, Edinburgh, Birmingham and Sheffield. Each has a fascinating history and offers some great insights and further reading online into this important part of the jewellery industry. Some even offer the chance to visit, which the team at C W Sellors would highly recommend should you get the opportunity.

What are the hallmarking keys?
When looking at a hallmark, it could be described as a jewellery registration plate and would typically include marks for sponsors, fineness, assay location and date. Although there are hundreds of registered hallmark elements, the selection below feature the standard/minimum set of hallmarks you would expect on a legal piece of jewellery sold in the UK

Hallmarking Keys 2020
Following a ruling by the European Court of Justice, the UK is required to accept other national hallmarks, for which there are 23 countries whose hallmarks are deemed equivalent to those of the UK. The British Hallmarking Council produced the full list online which can be viewed here.

Hallmarking - A Breakdown of Hallmarks
Since 1979, all pieces crafted in our workshop have been covered by C W Sellors long-held and reputable jewellers mark. This stamp has provided over 40 years peace of mind to anyone buying jewellery from C W Sellors’ high street boutiques and online.


Watch: What Is A Hallmark?

Watch: Why Hallmark?