Kansanshi copper mine is situated in the north western province of Zambia. As a result of the mineral variations, the processing plant treats three distinct ore types, viz, oxide, sulphide and mixed. The objective of this study was to investigate the floatability of a complex Kansanshi mixed copper ore with a special focus on the sulphidisation process. Controlled potential sulphidisation (CPS) is preferred over slug sulphidisation as the industry standard for the flotation of oxide copper minerals. Two potential ranges were investigated in this study; -300 to -400 mV and -400 to -500 my. Optimum flotation performance was observed in the potential range of -300 to -400 mV and a NaHS:SIBX ratio of 7:1 during CPS. An economic analysis of the results showed that CPS did not change the recoveries compared to slug addition but required much lower dosages of NaHS. (C) 2016 Elsevier Ltd. All rights reserved.