A method for the bacterially assisted heap leaching of chalcopyrite includes providing a chalcopyrite containing ore heap to oxidize sulphide minerals therein, the heap containing and/or being inoculated with a sulphide oxidizing bacterial culture that either does not oxidize ferrous to ferric, or is inefficient at doing so. At least a first leach solution pond (or other suitable container) is provided, from which feed solution is fed to the heap, and which receives leach solution from the heap. A portion of the leach solution is bled and passed to metals recovery.