The amount of compressive stress that a material is capable of sustaining before buckling or being crushed. If a material fails in compression by a brittle fracture, the compressive strength has a very definite value. Materials such as clay brick, cast iron, and concrete can exhibit great compressive strengths, but brittle failure results in a catastrophic failure. The crushing strength of concrete, called the cube strength because the test involves crushing a concrete cube, is around 6000 psi, granite is 20,000 psi, and cast iron ranges from 60,000 - 120,000 psi. In the case of ductile, malleable, or semiviscous materials (which buckle rather than shatter), the value obtained for compressive strength is an arbitrary value dependent on the degree of distortion that is indicative as failure of the material. Such arbitrary values are referred to as compressive yield strengths whereas complete compressive failure is termed ultimate compressive strength.