hi ,I have a silver brooch left me by a great aunt ...the usual 925 is there and what looks like...

a lower case i..however the only other marks are the letters REGD the D ha aline under it and bto the right of it what looks like 401by/w i cannot find an makers mark or where it was made ...can you tell me what these letters a nd numbers mean , i think its a design mark but cannot date this item ..is it english ?

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