Ann: Significant Further Copper Mineralisation Intersected, page-49

hkhf - you might like to check out the difference between copper sulphide minerals (chalcopyrite, chalcocite, bornite etc) and copper oxide minerals (cuprite, chrysocolla etc) when it comes to beneficiation (processing to separate out gangue (waste)).

The standard process for sulphide ores is froth flotation and it is well known and effective. Copper oxide ores are often found with copper sulphide ores and that is happening here. If a deposit contains more valuable sulphide ore than oxide ore, also as we are finding here, then often the oxide ore is separated out and left unprocessed. This happened with the chrysocolla found in Discovery Metals' ill-fated Boseto open pit mine nearby the Zone 5 UG mine. Apparently the oxide mineral cuprite can be processed via froth flotation but it is significantly more expensive, uncommon and recoveries are lower than with copper sulphides.