Victorian Shell Cameo Pin Lady Woman Flowers Filigree Brooch

Sweet piece - from my own collection - her hair is gorgeous skillfully carved flowers decorate her head. Check out her nose - I'm always critical of the nose. She is wearing a type of corsage on her dress - real shell - have to assume carved in Italy. There is a  tag bottom backside which reads 1-20D12KT. There is a movable loop for converting to a necklace which when folded down hides  when worn as a brooch. This piece has a rope like frame surrounding  the shell. There are 4 leaf medallions positioned around the frame.  This framework does show some age but the upper gold is pristine. See pictures 2 - 7 & 8. It has an unusual clasp.  I thought it was a Victorian slider however the barrel mechanism is stationary. The clasp is a roll-over to the left. See picture 4. All in all this is a great real shell carved cameo. Only one I have of course.