Antique metal lamp

This lamp is very heavy. Each piece shade and base are also very heavy indivisually. Similar shades on line call this butterscotch slag and amber glass. The metal base has carvings of flowers and decorative lines that are etched right on the surface of the metal. Some of the carvings seem to be fading away and Im not sure why. The edges of the open spaces in the base are rough, sharp, and jagged which makes me think it was manually created that way with hand tools not a machine. I dont believe the shade and base were made  to go together. I always find similar shades on line but they are always hanging lamp shades and they never exactly match the pattern of my shade. I have never seen another base like this one and I have searched for years, even the antique dealer I purchased it from has no idea.