Look over independent plant producing mineral (7)
I believe the answer is:
olivine
'mineral' is the definition.
(thesaurus)
'look over independent plant' is the wordplay.
'look' becomes 'lo'.
'over' says the letters should be written in reverse.
'independent' becomes 'i'.
'plant' becomes 'vine' (vine is a kind of plant**).
'lo' backwards is 'ol'.
'ol'+'i'+'vine'='OLIVINE'
'producing' is the link.
(Other definitions for olivine that I've seen before include "Dark green mineral" , "mineral in rock" , "stone" , "Clear green gemstone" .)