Hellenistic art
The art of engraving on gems hardly advanced at all, limiting itself to mass-produced items that lacked originality. As compensation, the cameo made its appearance. It concerns cutting in relief on a stone composed of several colored layers, allowing the object to be presented in relief through the effects of color.  After that it is mounted on a pendant or as a ring.  The Hellenistic period produced some masterpieces like the Gonzaga cameo , now preserved at the Hermitage Museum.