I have a gilded seashell imprint bowl marked: “ITALY 1847” with a porcelain coating on the inside (makes a high pitched gong sound when tapped) and what appears to be wood grain -underneath a red stain – underneath the gilding. Is this my imagination? The inside porcelain looks as if it were coil wrapped, but I suppose it may have been wood carved to appear that way… or maybe swelling of a tree’s rings. Any info is greatly appreciated thank you!