Columbus Stainless is based in Middelburg in the province of Mpumalanga. The company’s origins date back to the RMB Alloys Ferrochrome Pilot Project in 1963 and the establishment of Southern Cross Steel Co Pty Ltd (stainless steel) in 1964. In 1968 it became the Steel Division of Middelburg Steel & Alloys (Pty) Ltd (stainless steel and ferrochrome) and in 1990 MS&A Stainless (Pty) Ltd was established. Columbus Stainless was formed in 1991 when the initial partners, Samancor and Highveld Steel, acquired the stainless steel facility of MS&A Stainless from the Barlow Group. A major "brown fields" project, in and around the existing works, began in February 1993 and was completed in September 1995.

On 1 January 2002 Acerinox, SA (Spain) acquired a 64% shareholding in Columbus Stainless (Pty) Ltd. The remaining shares were held equally by Highveld Steel and Vanadium Corporation, Samancor and the Industrial Development Corporation. On 13 May 2005 Highveld Steel & Vanadium disposed of its investments in Acerinox and Columbus Stainless. Acerinox increased its shareholding in Columbus Stainless by 12% from 64% to 76%. The remaining shares are held equally by Samancor Limited and the Industrial Development Corporation.

Columbus Stainless’ product range of austenitic and ferritic grades is available in slab, plate, sheet and coil form in types 304/304L/316/316L/309/310/321/409/420/441/430 and 3CR12 and are normally manufactured to ASTMA240/A480 specifications but can be produced to all of the major international specifications on request. Columbus Stainless produces to South African Bureau of Standards specifications SABS ISO 001:2000 and SABS ISO 14001.