The sulphide enrichment gold deposit model best describes the mineralization of the Bradshaw Deposit.

The sulphide enrichment deposit model is characterized by a dominance of sulphide minerals over quartz veins, and is localized in shear zones adjacent to rheologically differing mafic to ultramafic volcanic rocks of tholeiitic petrochemistry. Mineralization typically comprises native gold associated with disseminated to massive arsenopyrite and vein hosted pyrite and arsenopyrite in silicified chloritic and sericitic schists, within a broad zone of potassium metasomatism and wall rock sulphidation (disseminated pyrrhotite and pyrite). Carbonatization of the wall rocks is a less conspicuous feature than silicification. Pervasive silicification and silicate alteration minerals developed within the shear zone consists of quartz, albite, chlorite, actinolite, tourmaline and amorphous carbon, suggesting a dominance of silicic and potassic alteration.

The Bradshaw Deposit comprises a geological Main Zone and several lesser Hanging Wall Zones. Gold mineralization in the Main Zone occurs primarily within a fractured and brecciated altered horizon previously interpreted as a shear zone in hanging wall basaltic flow rocks at or near the contact with steeply north-dipping (85°) footwall ultramafic rocks to the south.

Within the geological Main Zone, higher-grade gold mineralization is localized along the footwall of the horizon, termed the MZ1 Zone (previously referred to as M1 Zone - Harron, 2006) and occasionally along the hanging wall of the horizon, termed the MZ2 Zone (previously referred to as M2 Zone - Harron, 2006). Both gold mineralized zones appear to rake steeply to the east based on current drill data. Their variation in widths may reflect tectonically controlled shoots or boudinage structures.

Sporadic, anomalous to lower-grade gold mineralization is present between these subzones. Pervasive silicification, minor quartz-ankerite veining, hematite staining and presence of tourmaline generate a recognizable mauve to pinkish-grey hue for the mineralized zone. Total sulphide content of the mineralized horizon varies from 3-30% with occasional 2-5 cm wide bands of massive arsenopyrite and pyrite. Most of the sulphide component in the Main Zone is in the form of seams, bands and clots of sulphides accompanied by zones of heavy disseminations of 5-15% sulphides over 5-10 cm core lengths. The largest concentrations of arsenopyrite correspond to the highest gold concentrations. Visible gold is not a feature of this type of mineralization. Some late stage fracturing and brecciation of the mineralized horizon has caused varying amounts of sulphide remobilization (Roussain, 2004).

Similar mineralization forms multiple structures believed to be subparallel to the strike and dip of the Main Zone and are referred to as hanging wall zones as they are located immediately north of the main zone. They are highly silicified zones accompanied by intense bleaching, brecciation and quartz flooding, tourmaline, 5- 10% pyrite and arsenopyrite. The overprint of silica flooding and white quartz veining makes the hanging wall zones appear different from the Main Zone but the gold is associated with the sulphide component as in the main zone. As in the Main Zone, higher concentrations of arsenopyrite give rise to higher gold values. A total of six such parallel structures (HWZ1 to HWZ6) have been identified in locations and are significant contributors to the total number of ounces of gold contained within the overall Bradshaw Deposit.

To date, the deposit has a drilled strike length in excess of 950 m, trending N070-080°E, and has been tested to a depth in excess of 1,000 m. The horizontal width of the geological Main Zone varies from 2 to 22 metres. The Bradshaw zones are from 1 to up to 15 metres in horizontal width and average 2 to 3 metres. The deposit remains open along strike and at depth.

Overburden depth along the strike length of the deposit ranges from 10 to 16 metres and averages approximately 12 metres deep.

The Bradshaw Deposit is comprised of 8 steeply dipping (60-85 degrees) zones with a nominal thickness of 2-3 metres/zone and an overall strike length of 1,000 metres. The various ore zones are intermittent and discontinuous across the deposit, however, have continuity as sub economic mineralized sulphide horizons that can be followed along strike and down dip.

The longitudinal longhole (blasthole) stoping with unconsolidated and cemented crushed rockfill (waste rejects from the sorter) has been selected as the primary mining method. This will allow the level development to occur within the mineral wireframes, and any development connecting the various ore zones (which is below the cut-off grade) will be stockpiled as mixed development material at the entrance of the portal. This material will be later be put through the ore sorter in order to concentrate any potential gold material before sending to the mill.

Sublevels have been designed at 30 metre vertical intervals (floor to floor) compared to 20 metres in order to reduce development costs. On each sublevel, the deposit will be accessed from the centre and developed east and west along strike to a minimum size of 4 metres by 4 metres (allow travel of 6 yds LHDs). In most cases, an overcut and undercut will be developed to mine the deposit, but in some instances, only an undercut will be developed, followed by longhole uppers including inverse raising. Longitudinal mining will retreat from the outer limits back to the centre access point. The typical stope length will be 11 metres but may vary depending on proximity to the ultramafics. (Stope heights are normally 30 metres with some 20 metre and 15 metre uppers).

The flow-sheet design incorporates the following general stages:
1. Comminution (grinding and regrinding)
2. Sulphide flotation
3. Pressure oxidation
4. Cyanidation and gold refining
5. Cyanide destruction
6. Tailings disposal.

Crushed ore is hauled from mine site to mill by highway trucks of nominal capacities of approximately 34 tonnes each and transferred to a crushed ore storage bin at the plant site. The grinding circuit consists of a ball mill circuit. Ore is ground to a size of approximately 80% passing 75 microns prior to being sent to the flotation circuit.

A regrind mill circuit has been included to reduce the rougher flotation concentrate particle size to approximately 25 microns (P80) in order to improve the sulphide cleaning efficiency.

The flotation circuit consists of rougher and cleaner stages for separating the arsenopyrite and pyrite concentrates. The flotation circuit shown in Figure 17.1 represents the bench scale Locked Cycle Test (LCT) flow-sheet used in the metallurgical program (see Section 13). The rougher flotation is completed with a feed particle size of 75 microns (F80). The arsenopyrite rougher concentrate is then reground to 25 microns (P80) for final cleaning operations. The rougher tailings are fed to pyrite flotation stage for pyrite recovery, if required.

The sequential flotation circuit without applying ore-sorting generates two concentrate products:

- arsenopyrite concentrate (6.4%* mass recovery / 93% gold recovery);
- pyrite concentrate (4.8% mass recovery / 3% gold recovery).
*Note: With ore-sorting the mass pull for the arsenopyrite will increase marginally based on the higher feed grade of the sorted material.

For the standard flow-sheet, tailings from both arsenopyrite and pyrite cleaning circuits are combined and fed to the last stage of flotation, sulphide scavenger to recover residue sulphides prior to disposal. Flotation tailings will be separate from gold refining tailings management. Tailings impoundment will be located on site as a managed facility for life of mine operations.

Flotation concentrates are arsenopyrite and pyrite which are treated using pressure oxidation to oxidize the sulphides to access the gold in the solids.

The concentrate slurry is pumped into a continuously operating autoclave. Once in the autoclave, the slurry is subjected to high temperature (+200°C) and injected with high pressure oxygen from an oxygen plant. After about 60 minutes, approximate 98-99% of arsenopyrite and pyrite components in the concentrate dissociate to free the contained gold. The majority of the iron and arsenic is solubilized first and then precipitates under pressure forming scorodite ( FeAsO4·2H2O), a chemically stable form of arsenic.

The oxidized slurry from the autoclave is discharged, cooled and thickened separating solids from the acidic solution. A portion of the acidic solution from the thickener is recycled to the autoclave feed tank to help condition the new concentrate and remove carbonates. The balance of the thickener overflow is neutralized with limestone and lime prior to being pumped to tailings area. The thickened gold bearing POX residue is neutralized to a desired pH level suitable for cyanidation and then pumped to a cyanidation circuit for gold recovery.

Filtration of the thickened POX residue slurry prior cyanidation is being investigated, which will be necessary if the POX product is to be treated in a different location.

Neutralized POX residue is pumped a conventional CIL (Carbon-in-Leach) circuit where leaching and adsorption of gold are carried out simultaneously. Cyanide required for leaching gold is added to the circuit, while milk of lime is added to maintain slurry at the desired pH level. Barren activated carbon is added to the last tank and advances via carbon advance pumps counter-currently to the slurry. As the gold is leached, it is adsorbed by the carbon. Air is sparged from the bottom of each tank into slurry to maintain adequate dissolved oxygen levels in the pulp.

Carbon pregnant with gold from the first CIL tank is pumped to a loaded carbon screen where the loaded carbon is separated from the slurry. The slurry falls by gravity back to the 1st CIL tank. The loaded carbon is transferred to a bin from where the loaded carbon is transferred to the stripping stage.

Tailings from the last CIL tank overflows to a carbon safety screen which prevents the loaded carbon from getting lost. The screen undersize flows by gravity to a pumpbox, and is then pumped to the tailings dewatering area.

Cyanidation of the POX residue results in high gold extractions of over 98%. Loaded carbon is processed via a pressure stripping and gold refining plant. The expected overall recovery of gold from the ore is approximately 93%.