The Goldsmiths' Company Assay Office

The four wardens of the Goldsmiths’ Company were tasked with visiting workshops in the City of London to assay (test) silver articles.

It was not possible for the wardens to visit them all so the merchants were ordered to bring their items to Goldsmiths’ Hall for testing and marking and a permanent assay office was established in the building.

The hallmark indicates the amount of precious metal in the alloy in parts per thousand (the millesimal fineness).

In addition to hallmarking, the office has now expanded its range of services to support the jewellery trade and enforcement authorities.

It offers a variety of specialist analytical services including nickel testing, antique silver dating, non-destructive compositional analysis, plating thickness measurement and a melt and assay service for scrap precious metal carried out in their fully independent on-site laboratory.