I have a very similar ring made by A&W with same markings, except different letter next to the crown. It also has an M engraved on it so perhaps it is the ring size? Just a guess mins you.
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A&W by: Anonymous
Hi
The makers mark, A&W, is for Alabaster and Wilson.
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A & W Trademark by: Anonymous
Good Morning -
The Maker is:
Atkin & Wigley (Silversmiths, Birmingham, UK) ca 1920s. The crown followed by 22 is the UK gold standard for 22 carat gold in use for 130 years fin the UK, rom 1844 - 1974.
22 carat gold was the traditional choice for wedding bands during this time period.
The Anchor is the Birmingham town mark from 1773. The large letter M proceeding the series is an engraving and not part of the series.
The M at the end of the series is the date letter. You can find the exact year the ring was made by comparing the M inside your ring to the exact match in the list of Birmingham date letter marks by following the links on the Researching British Hallmarks page.