Copper Bronze Woman Portrait Pendant Hammered Intaglio Style Bas Relief 1800's

This is a very unique and lovely piece. I believe it to be either copper or bronze on top of another base metal. It definitely has a pretty shine. I polished it before taking these photos just lightly with a cloth. Likely made during the latter part of the Victorian era, during the art nouveau period, this has the hallmarks of both. The woman's hairstyle is certainly Victorian but the lovely flowers and vine that wrap around the bottom portion and to the side of the piece are art nouveau. It does have some surface wear to it. If you look closely you can see it has flecks of color loss throughout the surface of the pendant. These did not come out with my light polishing. I did not want to try and treat it any further for risk of damaging the patina. There is one spot on the edge of the pendant that seems to be a bit deeper and gray in color. I did test with a magnet and it was not at all magnetic. It measures approx 2" in length and 1.25" across with a thickness of 1/8". The only other thing I can tell you is that it came from an incredible collection where the woman was a dealer for 30 + years and traveled the country purchasing her pieces. Weighs 20 grams.