I have researched this piece and I believe it to have been carved by Tommaso Saulini....1793 - 1864????  He was an outstanding cameo engraver in Rome Italy. This cameo has all the subtleties of this carver and I have compared it to many of his carvings. Unfortunately the background of the carving is gone. Most of his cameos were signed to the right front side of the shell background.  So therefore, this piece has no signature!  It is very beautiful!  Measures 1 3/8"  x approx. 3/4" at widest. Excellent condition. I am including antique box. His treasured pieces sell for thousands of dollars!  You can Google for more information. I leave this up to your expertise!!!