Mineral pitch (7)
I believe the answer is:
asphalt
'mineral pitch' is the definition.
(synonyms)
This is all the clue.
(Other definitions for asphalt that I've seen before include "petroleum residue" , "Material for covering roads" , "Mixture of tar and gravel used in road surfaces" , "Bituminous material for roofing, paths etc" , "Road-buiding material" .)