MIM Holdings Limited was an Australian mining company created in 1970 as the parent company of Mount Isa Mines Limited, which operates the Mount Isa mines in north-west Queensland. Based in Brisbane, the capital city of the Australian state of Queensland, MIM Holdings owned and/or operated coal, gold, and base metal mines in Australia and Argentina. It also operated lead and copper smelters in Mount Isa, a copper refinery in Townsville (Queensland), a lead refinery at Northfleet (England), zinc smelters using the Imperial Smelting Process at the National Smelting Company located within Avonmouth Docks (England) and Duisburg (Germany), and a precious metals refinery in Sydney.