About Us

The International Association of Assay Offices (IAAO) is a forum for the exchange of information and promotion of technical co-operation between authorised state assay offices, with a view to provide a representative liaison body for communication with appropriate organizations.

 Assay offices are bodies responsible for the assaying and hallmarking of precious metals, such as jewellery and silver ware.

 The IAAO comprises 47 members from 37 countries. The IAAO works closely with the The Vienna Convention on the Control and Marking of Articles of Precious Metals. However, its membership is larger as not all members of the IAAO are members of the Convention.

The inaugural meeting of the IAAO took place on 15 April 2008 at Goldsmiths’ Hall in London. However, its history is longer than this and dates back to 1992. In this year, the Association of European Assay Offices (AEAO) was established, essentially with the same aims as the current organization.

The formation of the AEAO was a response to significant scrutiny of hallmarking legislation by the European Union as it attempted to harmonize services to create a single market. Providing a liaison body for European legislation remains a core activity. However, with the spread of interest in hallmarking beyond Europe, especially in the Middle East, Indian Subcontinent and Far East, many requests were made by assay offices from these regions to join the AEAO.

In particular, these assay offices were keen to participate in the technical co-operation programmes arranged by the AEAO. To reflect this globalization, the AEAO decided to change its name and modify its membership criteria to embrace these offices.

A typical examples of a Hallmark and a Convention Hallmark is shown below:

 UK National Hallmark

Order of marks: Sponsor’s Mark, Lion Passant (the traditional symbol for sterling silver), Fineness Mark for sterling silver (92.5% silver), Leopard’s Head (the symbol for the London Assay Office), Date Letter

 UK Convention Mark

Order of marks: Sponsor’s Mark, Common Control Mark, Finenes Mark for sterling silver (92.5% silver), Leopard’s Head (the symbol for the London Assay Office)