Black enameled medallion with diamond-set decorative monogram

Medaillon pendant with black enamel, decorative monogram set with rose-cut diamonds, backwards word of thanks and inside 2 glass frames, loop also with black enamel and rose-cut diamonds, 14K yellow gold, 28.5 g, 6x3.5 cm, 19th/20th century, enamel min. chipped, all in all age-related good condition.