Compulsory Marks

Modifications to the 1973 Hallmarking Act, effective from 1st January 1999, have changed the way articles made of precious metals are hallmarked. The UK hallmark now comprises a minimum of three compulsory symbols.

Sponsor's or maker's mark

Indicates the maker or sponsor of the article. In Britain, this mark consists of at least two letters within a shield, and no two marks are the same.

Metal and fineness (purity) mark

Indicates the precious metal content of the article, and that it is not less than the fineness indicated. Since 1999, all finenesses are indicated by a millesimal number (eg 375 is 9ct). This number is contained in a shield, the shape of which depicts the precious metal.

Assay Office mark

Indicates the particular Assay Office at which the article was tested and marked. There are now four British Assay Offices - Edinburgh,London, Birmingham, and Sheffield. There were other Assay Offices in former times.

Voluntary Marks

Traditional fineness (purity) mark

Prior to 1999, silver and platinum finenesses were indicated by symbols.

Date mark

Until 1999, a date letter indicating the year of hallmarking was compulsory. This is no longer so, but it can be applied voluntarily in addition to the compulsory marks.

Common control mark

This is a mark used by countries which are signatories to the International Convention of Hallmarks.

Commemorative mark

One example is the Millennium Mark which was applied to precious metals by the four UK Assay Offices during 1999 and 2000.

Another example is the Golden Jubilee Hallmark, graciously approved by HM The Queen to commemorate her Golden Jubilee. This was only the fourth royal commemorative mark in almost 700 years of hallmarking, and it was applied during 2002.