Vintage Marboux gold tone faux pearl brooch

Vintage Marboux gold tone faux pearl brooch . This vintage piece always reminded me of a seashell . Copyright symbol and Marboux stamped on the back with a number I think it reads 912 . Quarter and ruler in pics to help with size visualization. Questions are always welcome. Weighs 15 grams on my kitchen scale which equals ~ .53 ounces. Vintage , classic , Flaw see last picture on the back there is wear to the finish oxidization.