This plate is 520mm Diameter and is Labelled "J & G Meakin"
I believe it is Blue Flow and details on the rear state:
J & G Meakin
Hanley England
Reg:No:33283
Patented USA Oct 2 1900
It has small "pimples" on the perimeter and has a "4" impressed on the rear.
Stamp indicating J& G Meakin,etc as in previous script
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