Mother-of-pearl lampshade for hanging

Nice lampshade for hanging in mother-of-pearl surrounded by gold metal, simple and elegant. The lampshade must date back to the 1970s. It is in good general condition given its age, but has some spots and traces of use, or origin. The upper ring is black, perhaps a more recent repair. The lampshade is 24 cm larger in diameter and 13 cm tall and weighs 210 g. Some photos are taken with flash and others without.