The round back-stamp shows Royal Winton, Grimwades, Made in England and the letter “A”.
How the letter “A” is displayed is the clue letting me know when this teacup was produced in England.
In 1941 all potteries were required to be marked with the grade of it’s china.
It is at that time Royal Winton began adding the letter “A” to it’s pottery.
Royal Winton did not include this letter “A” in it’s script back-stamp between 1941 to 1951.
This new back-stamp continued until 1952. My teacup shows the letter “A” as part of the script back-stamp.
Sometime in 1952 the producers of pottery were no longer required to display the grade.