Inflammable material such as petroleum or asphalt (7)

I believe the answer is:

bitumen

(Other definitions for bitumen that I've seen before include "Substance for surfacing roads" , "Road-surfacing material" , "Material for road surfacing, roofing, etc" , "Road's topping" , "material that surfaces" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.