The project is located in the Dalgaranga Greenstone Belt in the Murchison Province of Western Australia. The North-East trending belt consists of high magnesium basalt, tholeiitic basalt, intermediate volcanic, felsic intrusive porphyry, and a volcano-sedimentary sequence dominated by black shale and volcaniclastic lithologies. The Greenstone sequence is intruded by large gabbro complexes in the north (Mt Farmer, Mt Charles) and to the west (Dalgaranga Hill). The stratigraphy has been folded into two regional synforms which plunge in opposite directions separated by a regional fault/shear along the western side of the Mt Farmer gabbro sill. The Dalgaranga Greenstone Belt is intruded by a number of post tectonic granites separated by zones of amphibolite and mafic schists intruded by pegmatites.

The main body of mineralisation is hosted by a porphyry - shale / volcaniclastic package and varies from 20 to 110 metres in width. A combined thickness of the main zone and parallel mineralised zones is up to 200m wide. The style of mineralisation at Gilbeys is a quartz pyritecarbonate veined ductile shear system.

The major control on mineralisation at Gilbeys is structure. A major ductile shear hosts the mineralisation, with the ore grade material developing as consistently wide sub parallel lodes in the areas of strongest shearing. A flat and late vein stage is visible in the footwall and ore-zone, these quartz + sulphide veins appear to be variably mineralised.

The operation is made up of two open pits; a single staged pit at Golden Wings and a two staged cutback of the existing Gilbeys pit, and a mining schedule developed to allow the process plant to process at the design capacity of 2.5Mtpa.

For extractive recovery testwork, samples were ground to 90µm and subjected to gravity separation followed by cyanide leaching. The porphyry samples were subjected to a timed direct cyanide leach and the shale samples were subjected to a 20 hour CIL leach. The RC composite samples from Gilbeys and Golden Wings were also subjected to a 20 hour CIL leach. The CIL leaches were utilised due to the presence of organic carbon in the samples and the 20 hour was based on the proposed plant residence time being 19 hours.

Significant amounts of gravity gold are present in all samples and gold leaching kinetics are very fast with the majority of leaching complete at 12 hours. Gravity gold recoveries at 90 µm grind from Gilbeys core samples ranged from 29.6% to 45.9%. Gravity gold recoveries from Golden Wings RC samples ranged from 26.7% to 71.1% at 90µm grinds. A conservative gravity recovery of 30% was utilised for FS design purposes.

The gold recoveries used for optimisation and financial modelling purposes are shown below.The recent testwork shows recoveries generally ranging from 91.1% to 93% for Gilbeys, and a consistent +96% for Golden Wings, dependant in location and material type, the fresh shale ore, which represents a small component (<10%) of the material in the mine plan has a lower recovery of 77%.

The process flow diagrams (PFD) for the Dalgaranga Feasibility Study (FS) have been developed from the process design criteria (PDC) prepared by Mintrex. The plant design proposed is simple but robust and broadly comprises the following:

• Primary Crushing;
• Crushed Ore Stockpile;
• Grinding and Classification;
• Gravity Recovery;
• Leaching and Adsorption;
• Elution and Electrowinning; and,
• Smelting.