I am re-furbishing a beautiful porcelain done in a similar style. If you can open the back; if you dare. You should see the Manufactures name. On the one I'm working on; the first thing you see is made in France with #'s under it.
After using a heavy duty magnifying glass on a stamp I came up with Japy Freres & CIE. If yours has this, then we'll go from there.
