When properly characterised, sulphide complex gold ores can be efficiently processed using a Gekko flowsheet design.
When gold is associated with sulphides, it can be either fully encapsulated by the sulphide particle or partially liberated, i.e. exposed on the edge of the sulphide mineral.
Sulphide complex gold can occur in a wide range of particle sizes. Because cyanide cannot always leach sulphide-associated gold, regrinding the ore is typically required to expose the free gold for recovery by intensive leaching.
Critically, the size at which one can efficiently liberate gold from the host mineral of the particle will determine the process to use for optimal gold recovery.