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Imports and Exports


If you are importing or exporting the Goldsmiths' Company Assay Office offers services to suit your needs. 

Our Heathrow sub-office was born from the goal to satisfy customers who operate on a world-wide basis.  Our partnership with Brink’s Global Services Ltd. ensures full liability coverage on precious metal articles from manufacturer through to assay and to their final destination via the world’s premier secure transportation network.

We are also able to accept international shipments at Goldsmiths' Hall thanks to our online submission service.  This enables the most efficient logistics chain with fewer steps in the process. 

For more information please contact Customer Service

Are UK hallmarks legally recognised overseas?

The "Houtwipper Agreement" was established by the European Court of Justice to enable mutual recognition of hallmarks between member states of the Hallmarking Convention. 

However, since 1 January 2021, the UK’s obligations to recognise other EU countries hallmarks has ended and, likewise, EU members’ obligations to recognise UK hallmarks has ended. (For Government advice about this please read this News article).

Subsequently, the broadest reaching hallmark that we can apply for you is an International Convention Hallmark. 

An International Convention hallmark applied in the UK is a hallmark comprising of either the 3 compulsory component legal marks, or the full five component marks of the traditional hallmark, plus an additional mark called a Common Control Mark. 

This allows sales of precious metal items within countries which are part of the Hallmarking Convention.

The Convention Hallmarks

Image 1. This Convention hallmark shows 3 compulsory component legal marks plus the 925 Common Control Mark to indicate sterling silver.

Image 2. This Convention hallmark shows the full UK hallmark plus the 925 Common Control Mark to indicate sterling silver.

More information about the Convention Hallmark

The Convention on the Control and Marking of Articles of Precious Metals (known as the Hallmarking Convention) is an international treaty between Contracting States, which aims to eliminate trade barriers in the cross-border trade of precious metal articles.

Signed in Vienna on 15 November 1972, the Convention came into force in 1975. Its text was mainly drafted and negotiated in Geneva and London, and Goldsmiths’ Hall is widely considered the Convention’s ‘birth place’.

The UK has been a signatory to the International Convention on Hallmarks since its inception 1972.

 

Finenesses recognised under the Convention are:

  • Gold - 375, 585, 750, 916, 999.
  • Silver - 800, 925, 999.
  • Platinum - 850, 900, 950, 999.
  • Palladium 500, 950 and 999

Left to Right: Sterling Silver/Palladium 950/18ct Gold/Platinum 950/ Type 2 CCM, to be used in conjunction with Millesimal Fineness mark

  • International Convention mark; Sponsor’s mark, Common Control Mark, millesimal fineness mark, and assay office town mark.

    International Convention mark; Sponsor’s mark, Common Control Mark, millesimal fineness mark, and assay office town mark.

  • Common Control Mark

    Common Control Mark

  • 40th Anniversary of the Hallmarking Convention, Goldsmiths' Hall 2015

    40th Anniversary of the Hallmarking Convention, Goldsmiths' Hall 2015

  • Example of 18ct gold convention mark

    Example of 18ct gold convention mark

  • Silver pen by Ajoto

    Silver pen by Ajoto