- Paving brick - A mass composed of several bricks run together by the
action of the fire in the kiln. - Scoria or vitrified incombustible matter, formed in a
grate or furnace where anthracite coal in used; vitrified or burnt
matter ejected from a volcano; slag. - A scale of oxide of iron, formed in forging. - A kind of brick. See Dutch clinker, under Dutch.