Abstract: Comminuting media comprising a martensitic/austenitic steel which contains at least about 40 percent by volume retained austenite, a portion of which is work transformable to martensite. The steel contains sufficient alloy content such that the steel has a martensite start and finish temperature sufficiently low to allow partial transformation of austenite to martensite during quenching of the steel from the austenitic range, but leaving some retained transformable austenite. This steel is used as a comminuting media, the retained austenite transforming to martensite through working or abrasion of the comminuting media during use in a comminution process. The outermost volume of the comminuting media which forms the wear surface and which contains the retained austenite in an amount of at least 40 percent by volume comprises at least 25 percent of the total volume of the comminuting media.