Unique vintage Pearl costume necklace with shell pendant. (OLCC)

This very pretty and artistic nexklace is approx 10” total with shell pendant 2” and necklace portion 8”. Small hook clasp 3/4” pendant can be worn either way visible. One side has leaf outlined on both sides. I do not know what material outlines the whole pendant (shaped like a large leaf) has a brass color, please see pics.