Bitumen element

A black-brown, viscous petroleum residue used as a binder and waterproofing. Hardens to a brittle, dark brown solid. Though not the same, often referred to as tar or pitch, as in tar sands and tar pits.

Getty AAT: Any of various solid or semisolid mixtures of hydrocarbons that occur in nature or that are obtained as residues from the distillation of petroleum or coal. (AAT 300012976)