BLACK DIAMOND STANDARD is an electric-furnace-melted, water-hardening carbon tool steel with an excellent reputation for use as the standard in general shop tools requiring extreme toughness and resistance to shock and impact. In the lower carbon ranges (0.50-0.70% carbon), it is used primarily for tools such as pins, punches, hammers and sledges. Black Diamond may be expected to give uniform and consistent results, although no definite limits of case depth or grain size are regularly guaranteed. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, joining, and surface treatment. Filing Code: TS-281. Producer or source: Crucible Specialty Metals Division, Colt Industries.