The Sao Francisco mineral processing system consists of a three stage crushing plant and gravity concentration circuit combined with amulti-lift, heap leach operation. Test work and ongoing laboratory analysis shows that the majority of the coarse free gold is released at a crush size of 6 millimetres. This product from the crushing plant is fed to the gravity plant, where jigs, centrifugal concentrators and shaking tables are employed to recover the gravity gold. The crushed product greater than six millimetres and gravity circuit tails are trucked from a storage bin at the crushing plant direct to the heap leach pads.
At the heap leach pad area, the crushed ore is stacked using trucks with subsequent ripping by bulldozers. DLO is used to build ramps and create side buttresses on the pads. Following stacking and ripping, the ore is irrigated with a weak cyanide solution and the resulting gold-bearing solutions are collected in a lined pregnant solution pond prior to processing for recovery of gold. A conventional carbon adsorption facility (ADR) is used to recover gold from process solutions and produce a final gold doré. Gravity plant concentrates are also smelted to produce a doré. Lined excess and treatment ponds and a solution detoxification circuit are included to handle the large amounts of seasonal rainfall. Excess solution is detoxified and then discharged.