Hallmarking

What is Hallmarking?
Precious metals are rarely used in their purest form, but are usually alloyed with other metals for the properties, such as durability, workability and flexibility, needed to produce a desirable jewellery article. It isn’t possible to detect an article’s precious metal content by sight or touch. Therefore, it's a legal requirement in the UK to hallmark any item described as gold, silver, platinum or palladium by an independent Assay Office. The hallmark guarantees the precious metal content of the item you’re buying, giving you complete reassurance. A Full UK Traditional Hallmark comprises three compulsory marks and two optional marks:
1. Sponsor's Mark (compulsory):
2. Fineness Mark (Compulsory):

3. Assay Office Mark (Compulsory):
Tells you which Assay Office tested and hallmarked the article. There are four Assay Offices in the UK, each one holds its own hallmark symbol. There were other Assay Offices which bear a different symbol but they have since closed. This does not affect your jewellery authenticity in any way.

4. Traditional Fineness Symbol (optional mark)

5. Date Letter (optional mark): Shows the year in which the article was hallmarked.

Exemptions Not Requiring a Hallmark Articles weighing less than the following will not carry a hallmark:
Gold weighing less than 1 gram
Silver weighing less than 7.78 grams
Platinum weighing less than 0.5 gram
Palladium weighing less than 1 gram
The International Convention on Hallmarks
The International Convention on Hallmarks is an international treaty between contracting countries, which aims at facilitating the cross-border trade of precious metal articles. UK is a signatory to the International Convention. This means that UK Assay Offices can apply the Common Control Mark (additional optional mark) which will then be recognised by all member countries in the Convention. The member countries of the Convention are: Austria, Cyprus, Czech Republic, Denmark, Finland, Hungary, Ireland, Israel, Latvia, Lithuania, The Netherlands, Norway, Poland, Portugal, Slovak Republic, Slovenia, Sweden, Switzerland and United Kingdom. For more information about the International Convention Marks, please visit any of the UK Assay Office websites.