Well-produced paintings (4)
I believe the answer is:
oils
I believe this is a double definition.
'well-produced' is the first definition.
(I've seen this before)
'paintings' is the second definition.
(oil paintings)
(Other definitions for oils that I've seen before include "paintings?" , "Well-produced" , "Olive and sesame, for instance" , "Soil, oddly, used by painters" , "Liquids for frying" .)