Deposits in the Mount Lofty Ranges are subdivided into the Gumeracha-Lobethal region and deposits north of Gumeracha which include the Lyndoch deposits. On Eyre Peninsula, deposits are concentrated near Tumby Bay, with smaller deposits associated with the nephrite jade near Cowell. Talc mines at Mount Fitton, have been in continuous production since 1945. There has been no production from impure gritty talc near Yongala in the mid north nor from lenses of massive grey talc north of Olary.