2 main types of copper deposit are recognized. 1 of these is of low grade, near the base of the laminite sequences in the Woocalla Dolomite, probably of syngenetic origin, and is believed to be the oldest and primary kind of deposit. (Gully, MG 14 area lower horizon, Sweet Nell, Fair Nell) The second type of deposit is of higher grade and may have formed by residual enrichment of the first type, (Cattlegrid, East Lagoon, West Lagoon, Main Open Cut, House, Gunyot). They occur at the disconformity on top of the Pandurra Formation where pinching out of the Woocalla Dolomite allows Whyalla Sandstone to directly overlie the disconformity. They are the highest grade deposits and are generally stratabound.