Asphalt / Road Aggregate

Physical Properties

Hardness varies based on aggregate (typically 5-7 Mohs); Color: dark grey to black matrix with multicolored crushed stone; Luster: matte to oily when fresh; Structure: massive, clastic.

Formation & Geological History

Formed by the mechanical mixing of bitumen (petroleum-based binder) with crushed stone aggregates. While the minerals in the stones are ancient, the composite material is modern man-made infrastructure.

Uses & Applications

Primary material for road construction, pavement, parking lots, and roof shingles.

Geological Facts

Asphalt is one of the most recycled materials in the world; nearly 99% of asphalt pavement is reclaimed and reused in new projects.

Field Identification & Locations

Identify by its dark, tar-like matrix binding heterogeneous crushed rocks together. Found globally in urban environments and transportation networks.

Identified on: 4/29/2026

Mode: Standard