Bissa Group Properties are underlain by geology considered to be similar to that of other Birimian-age volcano-sedimentary sequences. Hence, this region is considered prospective for orogenic gold deposits, which typically exhibit a strong relationship with regional arrays of major shear zones.

The gold mineralisation is typically associated with regular networks of quartz veins containing subordinate amounts of carbonate, tourmaline, sulphides and native gold. In these deposits, the gold is typically free milling. Alternatively, the gold mineralisation can be also associated with disseminated sulphides in strongly deformed alteration zones. In the latter case, gold may be free milling but also refractory.

In Burkina Faso, the weathering is deep and typically results in extensive surface oxidation of bedrock to depths reaching more than 100m locally. In such areas, gold deposits typically comprise a surface oxide zone, an intermediate transition zone and a deeper fresh rock zone. Gold is typically free milling in the oxide zone.

The gold mineralisation consists of disseminated sulphides, sulphide stringers, quartz veining and attendant hydrothermal alteration and quartz breccia bodies developed in highly strained sedimentary and volcanic rocks, loosely sub-parallel to the dominant foliation fabric of the Sabce shear zone.

The operation envisages open pit mining at an annual rate of approximately 3Mtpa, utilising drill & blast with a truck and shovel approach to ore and waste haulage.

A CIL process route was proposed for the Bissa mine at a nominal rate of 3Mtpa, although the new design target throughput is nearer to 4Mtpa.

The Bissa process flowsheet consists of a conventional carbon-in-leach (CIL) design involving fine grinding of the ore followed by leaching of the gold in agitated tanks using sodium cyanide.

The gold is initially removed from the solution using activated carbon after which it is stripped and recovered onto steel cathodes using an electrolytic process. These cathodes are then melted, refined and poured into gold doré bars.

Run of mine ore will be delivered to the plant by truck where it will be discharged into a hopper equipped with an 800mm trash screen. Oversize will be broken up using a hydraulic breaker.

From the hopper, material will be fed using an apron feeder onto a 150mm aperture grizzley with all oversize material reporting to a single toggle primary jaw crusher. The jaw crusher will crush thi ........