TL;DR The town mark on British or Irish silver names the assay office that tested it: leopard's head for London, anchor for Birmingham, crown or rose for Sheffield, castle for Edinburgh, tree and fish for Glasgow, wheatsheaves and sword for Chester, harp and Hibernia for Dublin. Each office ran its own date-letter cycle until 1975.
The town mark tells you which assay office tested a piece of silver, and you need it before a date letter means anything. An "a" from London and an "a" from Birmingham can be decades apart, because each office ran its own alphabet on its own calendar until the four remaining UK offices adopted one shared date letter in 1975.
Which assay office mark is on my silver?
Match the town mark to the office. A leopard's head is London, an anchor is Birmingham, a crown or a rose is Sheffield, and a castle is Edinburgh. A tree with a fish and a bell is Glasgow, three wheatsheaves around a sword is Chester, and a crowned harp with a seated Hibernia figure is Dublin.
| Office | Town mark | Marking |
|---|---|---|
| London | Leopard's head | 1300 to today |
| Birmingham | Anchor | 1773 to today |
| Sheffield | Crown, then rose (1975) | 1773 to today |
| Edinburgh | Castle | 1457 to today |
| Glasgow | Tree, fish and bell | 1819 to 1964 |
| Chester | Sheaves and sword | 1701 to 1962 |
| Dublin | Harp and Hibernia | 1637 to today |
Each office page below explains its marks, its date-letter cycles and the details that catch people out.
How did date letters differ between assay offices?
Until 1975 every office ran its own date-letter cycle, starting on its own day of the year. London changed letters in May, Birmingham and Sheffield in July, and Chester in July or August depending on the period. Cycles ran from about 17 to 26 letters. From 1975 the four UK offices share one letter that changes on 1 January.
Two later changes matter for modern pieces. Since 1999 the date letter has been optional in the UK, though most pieces still carry one. And since 2013 UK offices may strike hallmarks abroad; Birmingham has marked work in India since 2016, so a modern town mark no longer proves the piece was tested in that city. For a letter-by-letter walk-through, see the date letter lookup and British date letters guide .
Which assay offices have closed?
Chester closed on 24 August 1962 and Glasgow on 31 March 1964, leaving London, Birmingham, Sheffield and Edinburgh in the UK. Dublin still operates in Dublin Castle. Earlier English provincial offices such as Exeter, Newcastle, Norwich and York closed long before; their marks belong on English silver hallmarks .
Key takeaways
- The town mark names the assay office; read it before trying to read the date letter.
- London, Birmingham, Sheffield and Edinburgh still operate; Chester closed in 1962 and Glasgow in 1964.
- Each office ran its own date-letter cycle until 1975, when the four UK offices adopted one shared letter.
- Sheffield switched its silver town mark from a crown to a rose in 1975.
- Dublin is outside the UK system; its Hibernia mark now appears on everything it hallmarks.
Sources
- Hallmark, Wikipedia
- The Goldsmiths' Company Assay Office: history of hallmarking
- Sheffield Assay Office: history
- Birmingham Assay Office, Wikipedia
- Assay Office Ireland: history of the assay office
- Glasgow hallmarks (date tables after Jackson, 1921)
- Chester hallmarks (date tables after Jackson, 1921)
Frequently Asked Questions
How many assay offices are there in the UK?
Four: London, Birmingham, Sheffield and Edinburgh. Chester closed in 1962 and Glasgow in 1964, and the older English provincial offices at Exeter, Newcastle, Norwich and York closed earlier. Ireland's office in Dublin Castle is separate from the UK system and still operates under Irish law.
Why do date letters need the town mark?
Each assay office ran its own alphabet on its own timetable until 1975, so the same letter in the same style can mean different years at different offices. The town mark tells you which office's table to read. Without it, a single letter can point to several dates decades apart.
Do all British hallmarks have a date letter?
Not since 1999, when the date letter became optional in the UK. The compulsory marks are now the sponsor's mark, the fineness mark and the assay office mark. Most pieces still carry a date letter because buyers expect it, but its absence on a post-1999 item is legal.
