Medallion (silver, enamel)
 

Dear friends, the list what you think ...
1. the name of this kind of "Medallion"
2. that the stigma attached to the eye of the medallion, or even a stamp
3. approximate the estimated value

This family locket, whose history is traced from the end of XIX century.

I would appreciate any information.

Western Europe (France?), Worth tens of euros ...