Submicroscopic gold particles are evenly distributed throughout carbonate host rocks. The two principal lithological units are a sheared and altered thinly-bedded calcareous siltstone and Quaternary alluvium varying from chert, argillite, siltstone, limestone and quartzite to fine sands and silts. Proven and probable ore reserves at December 1998 contained 9.0 Moz of gold , with a further 4.95 Moz contained in measured and indicated mineralised material. These are capable of supporting an 11-year mine life. Pit wall slopes vary from 34 to 50 .
Mining is carried out with electric shovels, a hydraulic shovel and haul trucks.
A pit dewatering system including 40 wells helps to prevent water inflows, the water being transported from the pit to a series of shallow infiltration ponds for recycling. Discharge from the AG mill is screened, with screen oversize being conveyed to a cone crusher and recycled to the AG mill. The CIC circuit consists of six carbon columns with a retention time of 18 minutes. After stripping the carbon using a pressurised Zadra process, the gold is recovered by electrowinning on to stainless steel wool cathodes. The jewel of the Cortez Joint Venture, Pipeline will have PDG's lowest costs.