Can anyone help me identify this plate please, thank you.
As this is electroplated and not silver (EPNS = electroplated nickel silver) the answer to your implied question about value is “not a lot”. With electroplate condition is everything and any loss of plating will cause a loss in value. Note that nickel silver, the base metal here, is a similar colour to silver so plating loss may not be immediately apparent. For some idea of value see if you can find something similar in Ebay’s “Sold” section.
Phil
I will say I think the guilloché work is beautiful on the surface of that platter.