For the manufacture of jewellery and silverware precious metals are not used in their purest forms. Instead they are mixed with other metals like zinc and copper, known as base metals. The resulting mixture is what is called, an alloy. This is done to give greater strength, durability or a particular colour to the metal.
It is not possible to discern by sight or by touch how much precious metal, if any, is present in an alloy. It is therefore a legal requirement, in the UK, to hallmark all articles consisting of gold, silver, platinum or palladium (subject to certain exemptions) if they are to be described as such.
Precious metal is expensive. If you buy an item which contains less precious metal than it should, then you are being cheated.
The hallmark is your guarantee so you know what you are buying.
It is an offence under the UK Hallmarking Act 1973 for any person in the course of trade or business to:
• Describe an un-hallmarked article as being wholly or partly made of gold, silver, platinum or palladium.
• Supply or offer to supply un-hallmarked articles to which such a description is applied
How is the precious metal content of an alloy measured?
Gold alloys are graded by carat. The higher the carat, the greater the proportion of gold is in the alloy, up to a maximum of 24 carat (pure gold).
What needs to be hallmarked?
Any article described as being wholly or partly made of gold, silver, platinum or palladium that is not covered under exempt articles.
Articles below a certain weight are exempt from hallmarking. The exemption weight is based on the weight of the precious metal content only, excluding, for example, weight of diamonds, stones etc., except in the case of articles consisting of precious metal and base metal in
which case the exemption weight is based on the total metal weight:
• Gold 1.0 grams
• Silver 7.78 grams
• Platinum 0.5 grams
• Palladium 1.0 grams
What does a Hallmark look like?
A hallmark can only be applied by an independent Assay Office.
A Hallmark is made up of 3 compulsory symbols:
1. The Sponsor’s or Maker’s Mark
This indicates the maker or sponsor of the article. In the UK this mark consists of at least two letters within a shield. No two marks are the same.
2. Metal and fineness (purity) Mark
Indicates the precious metal content of the article and that it is not less than the fineness of the article indicated. The fineness is indicated by a millesimal number and the metal type is indicated by the shape of the surround.
3. Assay Office Mark
Indicates the particular Assay Office at which the article was tested and marked.
There are now 4 Assay Offices in the UK - London, Edinburgh, Birmingham and Sheffield.
The Hallmark guarantees that the purity of the metal is at least that indicated by the Fineness Number.
There are also a range of optional symbols that can be applied alongside the Hallmark. These are:
The date letter is optional in addition to the compulsory marks. The date letter changes once a year on January 1st.
For earlier date letters check with the relevant Assay Office. Birmingham http://www.theassayoffice.co.uk/, Edinburgh etc
The Common Control Mark
The UK has been a signatory to the international Convention on Hallmarks since 1972. This means that UK Assay Offices can strike the Convention Hallmark which will then be recognised by all member countries in the International Convention. Conversely, Convention Hallmarks from other member countries are legally recognised in the UK. Articles bearing the Convention Hallmark do not have to be
re-hallmarked in the UK. The outline of the mark varies according to the type of Precious Metal.
Things to remember
Remember that if the mark does not have at least these three symbols then it is not a hallmark. In many cases the manufacturer may stamp a number inside to state the purity. This is not a hallmark.
Don’t be afraid to ask the seller if their products are hallmarked.
If you purchase jewellery without a hallmark there is no guarantee that what you have purchased contains any precious metal at all.
For more information visit www.bis.gov.uk/britishhallmarkingcouncil or give us a call on 0845 450 9334