As summarized by Thivierge (2008), much of the gold mineralization in the Ouahigouya district is either hosted by metasedimentary rocks associated with granodioritic to dioritic plutonic rocks or by the plutonic rocks themselves. The gold mineralization is associated with the presence of disseminated Fe-sulphide phases (mainly pyrite and/or arsenopyrite), quartz veining and hematitic alteration to epidotitic alteration. The evolution of the Goulagou, Rambo and Kao deposits appears to commonly involve the participation of syn-orogenic granodioritic plutonic masses. The Kao and Nami deposits occur within a plutonic body, the Rambo deposit occupies a plutonic contact zone, and the Goulagou I and II deposits occur peripheral to known or suspected plutonic masses. Smaller plutonic masses and dykes (diorite, quartz diorite and/or granodiorite) are present in the meta-sedimentary rocks and within the margins of the plutonic masses, and may represent structurally-controlled dyke networks associated with the carapace of the plutonic bodies. The development of progressive and retrogressive metamorphic minerals may be in part related to orogenic plutonism.

The Karma property deposits have characteristics of mesothermal, shear-hosted gold deposits associated with orogenic activity. Elements of stratigraphic control may result from mineralization/alteration being channelled along specific structural/lithological controls, such as competency contrasts between sedimentary and intrusive rocks, that have promoted porosity and fluid flow. The Karma deposits may be best described as structurally controlled, orogenic, hydrothermal deposits.

Robert et al.?s (2007) classification of orogenic gold deposits is restricted to deposits composed of quartz-carbonate veins and associated wall rock replacement, associated with compressional or transpressional geological structures such as reverse faults and folds. Orogenic deposits consist of variably complex arrays of quartz-carbonate veins that display significant vertical continuity, commonly in excess of 1 km, without any significant vertical zoning. The ores are enriched in Ag-As+/-W, with Au:Ag ratios >5. Other commonly enriched elements include B, Te, Bi, and Mo. The dominant sulphide mineral is pyrite at greenschist grade and pyrrhotite at amphibolite grade. Arsenopyrite is the dominant sulphide in many clastic-sediment-hosted ores at greenschist grade and loellingite (FeAs2) is also present at amphibolite grade. Mineralized zones are surrounded by carbonate-sericite pyrite alteration halos that are variably developed depending on host rock composition. At the regional scale a majority of deposits are spatially associated with regional shear zones and occur in greenschist-grade rocks, consistent with the overall brittle-ductile nature of their host structures.

Gold mineralization on the Karma property is controlled by shear-related veining and alteration, developed in two dominant geological environments: sediment-hosted and intrusive-hosted. Compilation, analysis, and evaluation of the exploration database have resulted in True Gold's identification of the Kao, Golden Arch, and Rounga mineralization trends on the Karma property.

Gold is strongly associated with silica sericite-carbonate alteration and veining. Sulphide minerals associated with mineralization consist predominantly of pyrite and arsenopyrite. A petrographic report by KCA (2011b) also identified minor amounts of chalcopyrite and covellite along with traces of bornite, chalcocite and sphalerite; however, these are rarely seen in hand specimen. Gold grains are generally less than 35 microns in size, with a low (about 1.5 weight percent) silver content, but may be as large as 300 microns and contain up to 20% silver (e.g. Rambo). Visible gold is known from all deposits but is not common. Gangue minerals of interest include clay, feldspar, quartz, dolomite, and hematite and goethite in the oxide and transition material. There is some carbon, at least a portion of which is organic.

The mining method utilized will be conventional open pit mining, similar to that used at many other operations in Africa. Medium size mining equipment will be used (for example 90 tonne capacity haul trucks) to meet the production requirements.

Three types of material will be mined in the open pits. These are oxides, transition, and sulfide rock, with the oxides being the least competent rock and sulphides being the most competent. The oxides and some of the transition materials will not require blasting during excavation. However, as the pits deepen, harder rock will be encountered and some degree of drilling and blasting will be required.

Up to two hydraulic backhoe type excavators will be used as the primary loading units for the fleet of up to fourteen 90 tonne capacity haul trucks. A wheel loader will be available to be used in some instances. Waste dumps will be developed adjacent to all the pits, however at GGI some waste material may be placed in the mined-out pit area.

In some of the pits, minor amounts of "preg robbing" material may exist. Preg-robbing material contains components that absorb some of the gold released in the leaching process. It is assumed that this material will be stockpiled and processed at the end of the mine operational life to minimize its impact on the heap leach process.

The proposed Karma process plant design will be based on gold heap leach technology, which will consist of two crushing circuits (for soft and hard ore respectively), agglomeration and stacking, heap leaching with cyanide solution followed by adsorption of the pregnant solution, elution and gold smelting. Services to the process plant will include reagent make up, storage and distribution, water and air supply.

The heap leach plant is required to process 4 Mtpa of oxide and transition ore for the recovery and extraction of gold, delivered from five separate open pit mines, namely: GGI, GGII, Kao, Rambo and Nami. Only a minimal amount of sulphides, extracted from Rambo and Nami pits, will be processed through the heap leach plant. Sulphide material from GGI, GGII and Kao cannot be treated through heap leaching due to its refractory nature.

There will be two separate crushing stations to treat the soft and hard ore. The soft rock circuit will be partially skid-mounted and moveable and will be supplied as a complete package from a vendor. The hard rock crushing plant will only be required intermittently when the more competent ore is delivered from the pit. The quantity of more competent ore will be minimal compared to the softer material that will be fed to the plant and as a result, the hard rock crushing plant will be moveable.

The soft rock circuit will produce a final product with a top size of 50 mm. This product will be achieved in a two stage crushing circuit employing a feeder-breaker and a double roll crusher.

An agglomeration drum will be used to eliminate fines in the ore prior to stacking on the heap leach pad. Cement will be used to bind the fine particles in the ore to produce competent agglomerates. Solution will be added into the rotating drum to maintain the critical ore moisture required for optimum agglomeration.

Agglomerated ore will be discharged onto the overland conveyor. The overland conveyor will transfer the ore onto a conveyor system which will deliver the ore onto the heap leach pad. Provision for a stack height of 20 m has been made in the heap leach pad design. The cells have been designed with a lift height of 10 m.

A leach period of 120 days has been allowed for normal solution flow. Barren solution will be sprayed across the stacked cell via the irrigation system and will dissolve the gold in the agglomerated ore as it percolates through the heap to the pad floor. The gold enriched solution will be collected and gravitate to either the intermediate leach solution (“ILS”) pond or pregnant leach solution (“PLS”) pond. Excess solution will overflow to the storm water pond.

While the first cell is being irrigated, the second cell will be stacked. The gold enriched solution from the intermediate leach solution pond will be pumped to the second cell to irrigate the agglomerated ore. The solution will be further enriched in order to achieve the desired gold content in the final pregnant solution. The pregnant solution will be pumped from the pregnant pond to the adsorption column.

Pregnant solution will be pumped into the bottom of the adsorption column where it will come into contact with activated carbon in each of the six stages in the column. The solution will then discharge at the top of the column as barren solution and will gravitate through sieve bends to remove any carbon before gravitating to the barren pond to be reused for irrigation on the heaps.

A batch of carbon, loaded with gold, will be extracted from the first stage of the column and will be hydraulically transferred via an eductor to the elution circuit. Carbon will be transferred between the column stages using eductors. The carbon from stage 2 will be transferred to stage 1 (bottom of column) after which carbon from stage 3 will be transferred to stage 2. This will be repeated until stage 6 carbon has been transferred to stage 5.

Fresh or reactivated carbon from regeneration will be added to stage 6 of the column via the dewatering sieve bend installed above the adsorption column to remove the carbon transfer water. The transfer water will gravitate back to the carbon transfer water tank for reuse.

Pressurized Zadra will be used as the elution method. A cyanide-caustic solution will be pumped through the elution column whilst being heated up via the heat exchangers. The pregnant solution will be directed to the electrowinning cells once the temperature exiting the column outlet reaches 130°C. The spent electrolyte from electrowinning will flow back to the elution area. This cycle will continue until the level of contamination becomes unacceptable.

At the end of the elution cycle the stripped carbon will be hydraulically transferred to the regeneration section and the system will be made available to treat the next batch of loaded carbon.

The eluate from the elution column will be directed to the electrowinning flash/cell feed tank where it will be distributed to the electrowinning cells. Gold will be plated onto stainless steel cathodes as sludge and the barren solution will be circulated back to the elution area. The loaded cathodes are removed periodically and the sludge will be washed off and collected in the gold sludge tank where it will be manually tapped off into a bucket and taken to the drying oven in the gold room for drying.

Eluted carbon will be transferred hydraulically to the eluted carbon holding tank. Carbon will be withdrawn from the eluted carbon holding tank by a screw feeder, which will discharge the carbon to a diesel-fired rotary kiln for thermal regeneration. Regenerated carbon will be quenched in the quench pan and will pass over a screen to remove fine carbon before gravitating to the eductor tank.

The gold sludge that has been tapped into the bucket will be loaded onto stainless steel trays. The tray will be placed into the drying oven, equipped with a mercury retort for removing mercury from the sludge. The dried sludge, once cooled, will be mixed with fluxes and smelted. The molten charge will be poured into bullion moulds and allowed to cool. The slag phase will be broken away leaving a relatively pure gold bar.