It looks to be a "spun" piece, and the center is a separate piece which may be flanged, then hammered-over to attach it to the bowl. If it were a mold, it doesn't look too stable to set inverted (open side up) to be filled with any sort of material (edible or not). Not to mention the size wouldn't feed many.
Given its size, and just venturing a guess, I'd be more apt to think something along the lines of a street or yard lamp. May have very well been an additional finial which attached to the small round center area.
Is it magnetic?