A *canglomerate* is a sedimentary rock composed of a mixture of angular clasts (pebbles, cobbles, and boulders) and the matrix (sand, clay, or other fine-grained sediments) between them. It differs from a conglomerate primarily in the angularity of its clasts. These have not undergone extensive rounding and are therefore more similar in shape to the rocks they were originally derived from. It often indicates a proximal or source-border environment.