Hi Louise,
This tastevin is French silverplate. French silver maker's marks are (from c.1810 onward) framed in a diamond shaped cartouche and would, of course, be accompanied by recognizable silver standard & guarantee marks. French silverplater's trademarks are framed within a rectangle and are sometimes accompanied by another rectangular mark indicating plate thickness, 1G in this case. I don't know the maker's mark, but the second 2 letters are the abbreviation for Freres - Brothers in English.
Regards, Tom
ps. To get a clear picture of how different these silverplate marks are from French silver marks, see ->
French Hallmarks