The Goldsmiths’ Company will host its 40th Anniversary Hallmarking Convention and the International Association of Assay Offices (IAAO) meeting at Goldsmiths’ Hall September 9-11.

This represents the biggest international event in hallmarking for years and a major undertaking for the Company and its Assay Office.

A gala dinner tonight (Sep 9) will include pikemen, musketeers and the Ogmore Vale Welsh male voice choir and a letter of congratulations by HRH The Prince of Wales will be read aloud at the event. Thursday will see the actual Convention meeting take place whilst the IAAO meeting takes place on Friday.


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’.

Participating States recognise that articles marked with the Convention’s Common Control Mark (CCM) are of a legal fineness and can enter their territory without additional control or marking. The CCM is the first international hallmark accepted not only in the Convention’s Contracting States but also in other countries, where it is recognised as a mark of quality.

The IAAO works closely with the Hallmarking Convention. The synergy is both practical and logical since the IAAO organised the round-robin inter-laboratory comparisons on behalf of the Convention. Participation in this type of programme is essential, not only for demonstrating competence in assaying; it is also useful when a laboratory is seeking accreditation to the international standards, such as ISO 17025: Competence of testing and Calibration Laboratories.

The members of the Convention are Austria, Cyprus, Czech Republic, Denmark*, Finland, Hungary, Ireland, Israel, Latvia, Lithuania, Netherlands, Norway, Poland, Portugal, Slovak Republic, Slovenia, Sweden, Switzerland and the United Kingdom.

*including Greenland

Croatia, Italy, Serbia, Sri Lanka  and Ukraine are in process of acceding to the Convention.

The IAAO, an unincorporated organisation, now comprises more than 60 members from over 40 countries.  Not all members of the IAAO are members of the Convention.