Check inside mineral for pigment (5)
I believe the answer is:
ochre
'pigment' is the definition.
(ochre is a kind of pigment)
'check inside mineral' is the wordplay.
'check' becomes 'ch' (I've seen this in other clues).
'inside' is an insertion indicator.
'mineral' becomes 'ore' (ore is a kind of mineral).
'ch' inserted within 'ore' is 'OCHRE'.
'for' is the link.
(Other definitions for ochre that I've seen before include "Yellow-orange colour" , "Yellow-orange hue" , "yellowy-orange" , "Chore (anag) - pale brownish-yellow" , "Yellow-red mineral from iron oxide used as pigment" .)