Chipped mixed media artwork (6)
I believe the answer is:
mosaic
'chipped mixed media artwork' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
This is all the clue.
Can you help me to learn more?
(Other definitions for mosaic that I've seen before include "Relating to Moses" , "Design of small pieces of colored stone or glass (6)." , "Decorative work of small hard pieces" , "Picture of small tiles" , "Picture/pattern in small coloured pieces" .)