Gold deposits in the West African metallogenic district, including those on the Sabodala Project and the company's adjacent exploration concessions, show many characteristics consistent with their classification as orogenic (mesothermal) gold deposits and prospects. In addition to the deposits in western Africa, these include some of the largest gold deposits globally of variable age, such as the Archean aged Hollinger and Red Lake deposits in Canada and Kalgoorlie in Australia. Orogenic gold systems are structurally controlled deposits formed during regional deformation (orogenic) events. The term orogenic refers to deposits sharing common origin in metamorphic belts that have undergone regional compressional to transpressional deformation (orogenesis), often in response to terrane accretion or continent-continent collisional events.

Orogenic gold deposits exhibit a range of styles dependent on metamorphic grade, setting, fluid type, and fluid/confining pressure. They often include spatially associated quartz shear veins, extension vein arrays, shear zone and disseminated sulphide styles. At greenschist grade, vein dominated styles such as those developed in the Sabodala district contain quartz-carbonate ± albite ± K-feldspar veins with up to 10% (pyrite ± arsenopyrite ± base metals) sulphides and associated Fe-carbonate albite, chlorite, scheelite, fuchsite and tourmaline as associated vein and hydrothermal alteration assemblages. Vein systems and shear zones are often semi-brittle in style, including both brittle veining styles (extension veins and fault hosted brecciated shear veins), which alternate with periods of ductile deformation, producing sequences of early folded and younger less strained vein systems during latter periods of regional deformation at peak to immediate post-peak metamorphic timing. Sigmoidal extension vein arrays are often present and are typical of the deposit style. This deposit type often also has great vertical extent providing potential for discovery of significant down dip and down plunge continuations of mineralized zones.

Principal structures on the Sabodala Mining Concession form a steeply west-northwest dipping, north-northeast trending shear zone network, which has previously been referred to as the "Sabodala Shear Zone". The north-northeast trending shear zones at Sabodala likely represent first and second order structures of regional scale to first order features such as the MTZ , while the northwest trending shear zones may be third order features that accommodate strain between these higher order features.

Gold mineralization at the Sabodala deposit occurs in a combination of occurrences. Continuous grey quartz shear veins along shear zone surfaces in the Main Flat and Northwest shear zones, in sets of quartz-carbonate-albite-pyrite extension veins, in coalescing extension and shear vein domains forming zones of quartz-carbonate matrix breccia, and in areas of pervasive tan to pink coloured carbonate-albite-sericite-pyrite alteration which surrounds and links between veins, shear zones and breccia. Multiple generations of veins are evident, but the most voluminous veining and alteration forms the youngest generations.

The Niakafiri East deposit consists of the former Niakafiri Main, Dinkokono, and Niakafiri Southeast deposits, which are located adjacent to and along strike from each other. Gold mineralization is located within the north-northeast trending Niakafiri Shear zone that extends across the Niakafiri East area. Gold mineralization comprises sets of quartz veins, shear veins and disseminated pyrite developed in the ultramafic-hosted carbonate altered ductile Niakafiri Shear Zone, steeply dipping to the west. Mineralization is generally concentrated in areas of both most intense strain, and most pervasive dolomite-sericite alteration where networks of quartz extension and shear veins are developed, often spatially associated with fine-grained pink felsic dykes that occur in close proximity to the mineralized shears. The intersection of north-northeast and north-northwest trending shear vein sets and associated fringing sets of steeply dipping, east-west trending extension veins defines steep northerly plunging shoots.

The Goumbati West deposit is located southwest of the Maki Medina and Kobokoto south gold deposits and is an extension of the Niakafiri West Shear. The gold mineralization at Goumbati West occurs within a 1.2 km long north-northeast trending shear structure. Goumbati West is a north-northeast trending gold in quartz vein system comprised of several zones occurring in a sequence of epiclastics and basalt.

Gora is hosted by a moderate to steep southeast dipping, northeast trending sequence of turbiditic sandstone, siltstone, carbonaceous siltstones, and mudstone which is at least locally overturned by tight to isoclinal folding which are consistently down facing towards the west.Veins dip between 45º and 55º to the southeast. Veins vary locally to several metres thick and typically are banded with grey and white quartz.

The Masato deposit is located several kilometres to the north of Golouma West, within a zone of highly magnetic mafic and ultramafic volcanics. The geology of Masato is dominated by a north-northeast-south-southwest (~020º) trending ductile shear zone several tens of metres in width. The shear zone fabric dips approximately 70º west with local areas of intense metre-scale folding. Some ultramafic rocks are affected by the shearing and commonly appear “greasy”, possibly resulting from alteration by talc and serpentine. Carbonate dominated alteration is relatively widespread; however, fuchsite is present in addition to the carbonate-quartzsericite assemblage, particularly within ultramafic units.

The geology of the Golouma area is dominated by moderately deformed massive flows and pillowed basaltic rocks. The rocks are moderately chloritized, which in some instances is accompanied by the development of epidote replacement. Hydrothermal carbonatedominated alteration overprints the rocks where deformed by ductile shear. In areas of low strain, the alteration yields a wispy appearance, but in more highly deformed zones, it imparts a buff or salmon-pink colouration and is associated with anomalous gold concentrations. Several felsic dykes, up to 5 m in width, occur throughout the Golouma area and appear to be intimately associated with the gold mineralization, particularly in Golouma South. A small number of mafic dykes have been recognized in drill core, including one larger gabbroic dyke approximately 12 m in width.

The Kerekounda deposit is located approximately 1.5 km to the north of the Golouma South deposit, within the same east-northeast-west-southwest structural trend that hosts the mineralization of the Golouma area. The deposit is hosted by weakly to moderately deformed mafic volcanics, similar to the host rocks at Golouma. The main ductile foliation orientation is 060-240°, consistent with the east-northeast trending regional structure.

Three distinct shear zones host the mineralization at Kerekounda. Each zone typically ranges from one metre to 10 m width and high-grade shoots plunge steeply toward the westnorthwest. The plunging shoots appear to be controlled by the intersection of the regional north-northeast trending shear zone fabric, which controls the location of mineralization in the Golouma-Kerekounda area, with the discrete north-northwest trending shear zones that host the mineralization. Of the three mineralized shears, it is the eastern most shear which is most prevalent. It comprises a quartz-carbonate vein and multiple veins and/or vein breccias, within a broader zone of carbonate dominated alteration. The highest gold grades occur with the quartz veins especially those containing tourmaline while lower grades are generally found in the adjacent altered rock.

Golouma South, Golouma West, Kerekounda, and Gora are currently being mined in the second half of 2017.

The mining method utilized is conventional truck and shovel open pit mining. The mining operation is effective at selectively separating ore from waste, and in separating the four ore categories that are stockpiled if not immediately milled.

C&F mining method for use at the underground Golouma deposits. The underground mine construction begins in year 2022, with ore production in 2023. The open pit mining ends in year 2027 and the remaining LOM comprises mining from the underground and stockpile reclaim.

The Sabodala processing plant was expanded in late 2012 to a design capacity of approximately 3.6 Mtpa (fresh ore) or 4.0 Mtpa with a mix of fresh and oxidized ore. In mid2015 a mill optimization project was initiated and commissioned in Q3 2016.

The mill optimization project consisted of adding a second primary jaw crusher and screening station to operate in parallel with the original crusher and upgrades to the primary and secondary milling circuits. Upgrades to the SAG milling circuit include installation of a trommel screen, redesign of the liner configuration, and installation of a vortex discharge head. Upgrades to the ball mill circuit included increasing the ball charge, increasing motor power by 500 kW for each ball mill, and installation of new gearboxes. The increased milling rate for hard fresh rock is in excess of 500 tph and approximately 530 tph for a blend consisting of fresh rock and soft oxidized ore. As a result, annual throughput rates for the plant are estimated to be in the range from 4.3 Mtpa – 4.5 Mtpa.

The plant comprises facilities for crushing, grinding, carbon-in-leach (CIL) cyanidation, and tailings disposal. Gold recovery facilities include acid washing, carbon elution, and electrowinning, followed by bullion smelting and carbon regeneration.

Rear dump haul trucks and front end loaders deliver ROM ore to two, identical primary crushing facilities (Crusher A or Crusher B) that are operated in parallel. Ore delivery from the mine is on a 24 hr/d schedule. A front-end loader feeds ROM ore to the ROM bins. From the bins, apron feeders deliver ore to the vibrating grizzly feeders. Oversize from the grizzly feeders discharges to the jaw crushers. Undersize from the grizzly feeders by-pass the jaw crushers. The discharge from the jaw crushers and the undersize from the grizzly feeders are combined and conveyed to triple deck screens that segregate ore into two particle size distributions. Conveyors transport screen oversize ore from both circuits to Stockpile 1, which is the coarse ore stockpile. Conveyors transport undersize from the screens to the secondary crusher bin that feeds the secondary crusher. Conveyors transport the secondary crushed ore to Stockpile 2.

Ore is ground in two stages to produce a product suitable for cyanide leaching. The first stage includes a SAG mill driven by a four megawatt variable speed motor. Ore is conveyed from the crushed ore stockpiles to the SAG mill feed chute where it is mixed with water to form a slurry. Lime is metered onto the SAG mill feed conveyor to control the pH to approximately 10.0. Slurry discharges from the SAG mill through a trommel screen and onto a vibrating screen. Oversize pebbles are crushed by the 132 kW pebble crusher and returned to the SAG mill feed conveyor. Undersize from the SAG mill discharge screen flows by gravity to the ball mill 1 primary cyclone feed hopper, where it is combined with the discharge from ball mill 1 and process water.

The leach circuit consists of three leach tanks and nine leach-adsorption tanks. The circuit residence time varies from approximately 24 hrs to 30 hrs, dependent on the ore blend. Sodium cyanide is added to the first leach tank. All tanks are sparged with low-pressure air to ensure sufficient oxygen is available for the gold dissolution reaction. Granular activated carbon is added to the slurry to adsorb the gold-cyanide ion. The carbon concentration is maintained between 10 kg/m3 and 15 kg/m3 in the adsorption tanks. Each stage of the adsorption circuit consists of a mechanically agitated tank equipped with a mechanically swept vertical carbon retaining screen. Slurry flows by gravity from the first tank in the circuit to the last tank (i.e., Tank 1 through Tank 9). Carbon advances countercurrently by pumping slurry from tank to tank on an intermittent basis in a flow that is opposite to the gravity flow (i.e., from Tank 9 to Tank 1).

The pregnant carbon is recovered from the adsorption circuit using the loaded carbon transfer pump. The carbon is screened and washed with process water on the loaded carbon screen and reports to the acid wash column where the carbon is washed with hydrochloric acid to remove the inorganic contaminants. After the acid wash, the carbon is rinsed with water. The rinsed carbon is transferred to the elution column.

To recover gold from the carbon, batches of carbon are subject to a high pressure and temperature elution process. Hot cyanide-caustic solution is used to strip the gold from the carbon and recover it into pregnant solution. Precious metal is recovered from the pregnant solution by electrowinning onto stainless steel wire wool cathodes in an electro-winning cell.

The loaded cathodes are removed from the electrowinning cells and washed with pressurized water to remove sludge that contains the precious metals. The sludge is then dried in a drying oven. The dried sludge is mixed with fluxes and smelted on site to produce doré that includes gold and silver. The "barren" carbon is thermally re-activated to remove organic contaminants and returned to the circuit.

The precious metal doré is shipped under secured conditions to the contracted refinery for further processing and subsequent sale.