The solidification of all ferrous alloys is accompanied by the phenomenon of contraction that can cause macro and micro shrinkage defects, which can form many discontinuities and eventually result in a complete fracture. Contrary to steel, cast iron benefits from the expansion of graphite during its precipitation. Such expansion partly compensates for any contraction. So cast irons, especially those with a high C.E., are much less prone than steel to shrinkage and provide better integrity to castings, notably those with irregular shapes and variances in wall thickness. For such reasons, in many cases, castings made with iron would not be feasible in steel.