asphalt

Definition

Dark brown to black, thick, viscous mixture of heavy hydrocarbons that occurs naturally (left after evaporation of lighter hydrocarbons, as in Trinidad's Pitch Lake) or as a residue of crude oil refining or destructive distillation of coal. Its ability to flow when heated, moisture repellency, and (depending on the type of additive) a range of softening points (usually between 57°C to 99°C, or about 135°F to 210°F) makes it an ideal material for road paving, roofing, and water proofing applications. Also called bitumen, coal tar, pitch, or tar.