The back is stamped with Chinese characters so it is clearly made in China. I think that the carved / molded glass stone with flowers and leaves (I have seen these sell as genuine coral although they are glass) was made in a mold in Czechoslovakia around 1920 and then just the glass was exported to China before the Chinese Cultural Revolution. If you google " Chinese Export Silver" you can see pictures of some of the early silver chop marks or stamps which look similar but I can not read to identify. The faux / simulated pearls are glass pearls and the outer paint / pearlescents is rubbing off with age. Overall beautiful, unusual antique pendant with a beautiful patina and in good condition, small hairline crack across the face of the pendant which I can only see under magnification.
The pendant looks antique brass tone from the front and the back and bail look silver. I think the pendant is vermeil / gilded 600 silver - 600 silver is 600/1000 parts silver (Sterling is 925/1000 sterling). There is no acid test for low silver so I can not verify this. The pendant itself is not magnetic. Damage: There is a hairline crack across the face of the cabochon.
Please ask me if you have any further questions.