Die, Diamond

A wiredrawing die made from one of the forms of diamond. They are more expensive than carbide dies but wear longer and are often used for drawing finer wire sizes. Industrial diamonds often draw to 0.005 to 1 mm (0.002 to 0.04 in.) for harder wires and up to 2.5 mm (0.1 in. for copper. They are specified in B.S. 2946, which deals with quality of the dia­mond, the mounting, casing, size tolerance and marking. See entries for Die, Diamond Natural; Die, Synthetic Single Crystal; and Die, PCD Diamond.