What is a Hallmark?
If you are a retailer, importer or craftsperson and you are placing precious metal items onto the market, you have a legal obligation to ensure these items are hallmarked. If you are a consumer buying a precious metal item, understanding hallmarking can help you to make informed decisions. This page provides useful information for consumers, makers and businesses about how to read and recognise hallmarks. Further information about specific hallmarking requirements, pricing and other guidance can be found in our Downloads & Resources section.
A hallmark is a series of marks applied to an item of precious metal by an independent, government-appointed Assay Office. There are currently four Assay Offices in the United Kingdom: Edinburgh, London, Sheffield and Birmingham. Hallmarks can only be applied to an item after it has been tested through a process known as ‘assaying’, where the precious metal content is verified.
A hallmark protects consumers when purchasing items made of precious metal. Precious metal jewellery is normally made of an ‘alloy’, a mixture of precious metal and lesser metals. It is impossible to tell how much precious metal is contained in an alloy based on sight or touch alone. Therefore, assaying is the only way to confirm the precious metal content of an item reflects what is advertised. Consumers have a legal right to the independent guarantee that a hallmark provides, and sellers are legally required to ensure relevant products are properly hallmarked.
Are you selling precious metal jewellery?
Register with Edinburgh Assay Office to begin your hallmarking journey.
What does a Hallmark tell you?
Who?
The registered mark of the company or individual who placed the items on the market.
How to Read a Hallmark
Compulsory Marks
A hallmark can only be applied by a government authorised Assay Office, such as Edinburgh Assay Office. A hallmark includes 3 compulsory symbols: The Sponsor’s or Maker’s Mark; Metal and Fineness (purity) Mark; and the Assay Office Mark.
The Sponsor’s Mark or Maker’s Mark (Who?)
This mark indicates either the maker or the company/person who has sponsored the item through the hallmarking process. In the UK, this mark consists of at least two letters within a shield. No two sponsor’s marks are the same.
Metal and Fineness (purity) Mark (What?)
This mark indicates the precious metal content of the alloy used to make an item. This confirms that the alloy is not less than the fineness indicated, such as 925 silver. The fineness is indicated by a millesimal number (parts per thousand) within a shape. The shapes indicate the metal type of the item.
Assay Office Mark (Where?)
This mark indicates the Assay Office where the item has been tested and marked.
Voluntary Marks
Traditional Fineness Symbols
Traditional fineness symbols representing sterling silver, Britannia silver, palladium, gold and platinum. These cannot be used in place of the required Metal & Fineness Mark.
The Date Letter
Until 1999 the Date Letter was compulsory. This is no longer the case, but it can be applied voluntarily in addition to the compulsory marks. The date letter changes once per year on 1st January.
The Common Control Mark & Convention Marks (CCM)
Since 1975, the UK has been a signatory to the International Convention on Hallmarks. This means all UK Offices can strike the Convention Hallmark and this is recognised by all other signatory countries to the International Convention. Equally, Convention Hallmarks from other member countries are legally recognised in the UK. This means that items bearing the Common Control Mark (CCM) in addition to national marks do not have to be assayed and re-hallmarked before they are placed on the market in any of the 22 contracting states.
There are 2 types of Convention Mark:
Type 1
In this mark, the number indicates the fineness of metal between a set of scales, and the shape indicates the metal type.
Type 2
This mark displays the scales only and is the same shape on all metals. Additionally, items displaying this Type 2 mark must also have additional marks indicating the metal type and fineness. These can be a chemical symbol or shield indicating the nature of the precious metal and Arabic numerals indicating the fineness.
Below are the types of fineness recognised under the International Convention on Hallmarks:
Platinum: 850, 900, 950, 999
Palladium: 500, 950, 999
Gold: 375, 585, 750, 916, 990, 999
Silver: 800, 925, 958, 999
Below is an example of a Convention Hallmark, consisting of 4 compulsory marks: The Sponsor’s or Maker’s Mark; The Common Control Mark; The Fineness (purity) Mark; and the Assay Office Mark.
