Vintage jewelry

Vintage viktorian cameo jewelry, which can be placed on the chest or hung on a necklace chain. The material around is some metal and I do not know the material of the woman's figure. However it is not plastic, rather glass. Inside the jewelry there is also some stamp etc. It would appear to be the letters WMCA (last picture). The age of the jewelry is not known, but apparently old. Height approx. 5 cm and width approx. 4.5 cm.