Help with hallmarks on old Sheffield plate wine coaster

Hi all. Can anyone help i.d. the hallmarks on what I believe to be my old Sheffield plate wine coaster? Thanks for your thoughts.

This is electroplate, not Old Sheffield Plate. The manufacturer is Elkington & Co of Birmingham. The “7” in the lozenge is their private date code for 1847 so this is a very early example of electroplate.


Thanks so much Phil! Appreciate the info and help.