is a highly viscous liquid that occurs naturally in most crude petroleums. Asphalt is separated from the other components in crude (such as naptha
) by the process of fractional distillation
. It is sometimes confused with tar
, which is an artificial material produced by the destructive distillation of organic matter. Both tars and asphalts are classified as bitumens, a classification that includes all materials entirely soluble in carbon disulphide.
Asphalt is commonly used in roofing shingles, and combined with mineral aggregate to make Asphalt concrete.