It might make a cameo (4)

I believe the answer is:

onyx

(Other definitions for onyx that I've seen before include "Mineral with coloured layers" , "Quartz with alternating bands of colour" , "Form of quartz" , "Variety of agate used for making cameos" , "Hard stone with coloured layers" .)

I've seen this clue in The New York Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.