I have looked for your mark and have not found any mfr. who used this as a factory marking !! That is not surprising,, many sets like this are unmarked !! My best guess is that it is early 1900`s but exactly when it was made or by who is unknown !! The AO7 on the bottom is likely a style number and would only be useful to those making the sets !! Sorry but that is about all I can help you with !! Its very pretty,, is it a family item ??
