Abstract: A method of manufacturing a cast ferrous metal die wherein an initial die of non-ferrous metal is cast in a mould against a basic metal pattern having a melting point substantially not less than that of the non-ferrous casting metal, the basic metal pattern being preheated and coated with refractory material and the non-ferrous casting metal is cast against the preheated and coated basic pattern in a supercooled condition to minimise thermal shock and heat transference between the casting metal and basic pattern, and forming a further corresponding pattern of refractory material in the initial die, and then using the pattern of refractory material in a mould for casting a cast ferrous metal die from said refractory pattern, the cast ferrous metal die so obtained being of corresponding accuracy to the basic metal pattern.