Vintage Cameo Necklace Princess Length Silver Setting Acanthus Leaf

Vintage to antique acanthus leaf cameo necklace. Hand hewn cameo and backing (see photo closeups), cameo has non-smooth surface, feels like and sounds like stone on testing, indicating stone or shell. I believe the setting is silver, appears to be hand hewn also. It is missing a few of the little green stones. No maker's mark seen. The cameo itself is very small it is appx 1/2" long and cameo within lower setting is approximately 1-1/4" x 1" The leaf setting with cameo setting are appx 2-1/2" long. Chain length 6-1/2" making total length 9-1/4" (princess length which sits on the collarbone). It is very dainty, very beautiful. I believe the setting is silver or silver plate. It is nonmagnetic and polishes, though I did not polish it completely as I didn't want to damage the stones. I think these are tiny green rhinestones, which also were used in many pieces in late 1800s. The chain I believe is newer, it seems a more modern look than the pendant itself. Selling as is. Needs professional polishing I would think to being out its luster.