Taps into valuable material to make pigment (5)
I believe the answer is:
ochre
'pigment' is the definition.
(I know that ochre is a type of earth color)
'taps into valuable material' is the wordplay.
'taps' becomes 'ch' (cold and hot taps).
'into' means one lot of letters goes inside another.
'valuable material' becomes 'ore' (ore is a kind of material. I am not sure about the 'valuable' bit.).
'ch' placed within 'ore' is 'OCHRE'.
'to make' acts as a link.
Can you help me to learn more?
(Other definitions for ochre that I've seen before include "Chore (anag) - pale brownish-yellow" , "Orange-yellow colour" , "Gold coins, perhaps" , "Red or yellow pigment" , "Golden pigment" .)