Artist's range of colours (7)
I believe the answer is:
palette
'artist's range of colours' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for palette that I've seen before include "Artist's range of colours" , "An artist mixes his paints on it" , "Artist's colour-mixing board" , "selection of colours" , "Painter's utensil" .)