Hi Yuki,
Thanks for posting. The date marks for London only apply to London made articles. Most of the larger English cities had their own assay offices, with their own sets of date mark letters. However, the Online Encyclopedia of Silver Marks, Hallmarks & Maker's Marks (OES for short) does have date charts for a number of different cities in England, Ireland and Scotland. Included are London, Birmingham, Chester, Dublin, Exeter and Edinburgh. Links to all of these date letter charts can be found at
British HallmarksGlasgow, Newcastle, Sheffield and York do not yet have charts illustrated, but they should all be up within the next few months.
The quick and easy way to get a general date on a piece made between 1784 & 1890 is to look at the sovereign's head mark. These are also illustrated on the British page.
Tom
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