Would appreciate any guidance on these sconces


I am new to the forum, and so pleased to have found it. It would be much appreciated if anyone could offer some guidance as to age / value of these sconces. I believe they are silver over copper, and might be Sheffield. They are not wired for electric. The candle section has 3 arms, which detaches from the wall plate.

Many thanks and best wishes for the new year.
sconce markings.jpg