Engraved gem (5)
I believe the answer is:
cameo
'engraved gem' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cameo that I've seen before include "relief work" , "Carved brooch - small role" , "Small role in film" , "Ornament or miniature performance" , "Short performance" .)