Ambitious construction projects, particularly those of monumental proportions, required large amounts of stone. Quarrying provided the solution, with ancient engineers using the natural fault lines found in granite to split blocks from the bedrock. Once such a crack had been found, a large labour force was employed to pound the fault line, in order to weaken the rock further. These men carried sledgehammers made from rounded blocks of dolerite, a substance harder than granite. The process was accelerated further when it was discovered that rock which was heated with fires and then cooled by having water poured on, expanded and contracted. This made it split along any weaknesses such as cracks.
