Birmingham Assay Office. Since the 14th century in Britain articles of silver and gold have had to be tested at an assay office for metal purity standard and there hallmarked to protect the customer from fraud. Until the 1750s Birmingham's silversmiths and jewellers had to send their goods to London or Chester assay offices, which was inconvenient and expensive. Matthew Boulton campaigned for Birmingham to have its own Assay Office. In 1773 the first Birmingham Assay Office was opened on New Street. At first only silver was hallmarked not until 1824 could gold be marked with the Birmingham anchor mark. The Assay office has been in the present building since 1878.