I've just read that France also used a quality mark of a "crowned F" for fine pewter, do not know what forms the mark takes. Not sure which pewter organization you've contacted, but here is an inquiry email
enquiries@pewtersociety.orgPlease let us know what you learn about the piece.
if the arms are from the Duchy of Brittany and the motto that of Anne, I doubt they would appear on a pewter plate.
Let's not forget, no matter how grand a household, the stable hands and scullery maids were not eating off of silver, nor pewter for the matter, they were probably lucky to get a wooden bowl, but somewhere up the ladder there were folks within the household that rated a pewter plate.
Regards, Tom
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