The date letters referred to below show the background shape for silver. The same letters were used for Gold, which has been marked at Assay Office Birmingham since 1824, but with a background of a square with cut corners. There may be some variations in backgrounds during the late 19th century, especially on watch cases.
In Birmingham, the date letter changes in July up to 1974. From 1975, all Assay offices have the same date letter.
Depending upon the font used for the series of date letters, the letter i, j or l is usually omitted to avoid any possible confusion between them. As a result the date letter cycle is usually 25 years as opposed to 26. For example, due to the very simplistic font currently in use, it was decided that the letter ‘i’ should be omitted in 2008, with ‘j’ used instead and ‘l’ used in 2010.
Click here to see the date letters from 1773.