Your lovely cameo appears to be a disciple of the the Art Nouveau era.
Art Nouveau Jewelry was produced between 1895 -1910. The Natural world, which included botanical themes were inspiration for the Art Nouveau jewelry.
Fire damage, could possibly be Age patina. What makes you suspicious?
Do you have any ideas what the piece might be made from? ...does it have the weight of metal, or does it feel lighter in the hand.. more like plastic or synthetic material? More details are needed to further comment....
