The Haile district consists of nine gold deposits within a 3.5 km by 1 km area. Haile occurs within a variably deformed ENE-trending structural zone at or near the contact between metamorphosed Neoproterozoic volcanic and sedimentary rocks. Haile is hosted in laminated siltstones and minor volcanic rocks of the Upper Persimmon Fork Formation and is dissected by barren NNW-striking diabase dikes. Deformation includes brittle and ductile styles with ENE-trending foliation, faults, brecciation, and isoclinal folds.

Foliation intensity increases along sedimentary-volcanic contacts and is strongest in the laminated siltstones where gold mineralization is best developed. Gold-pyrite-silica-rich fluids were preferentially precipitated in more permeable and structurally deformed metasediments. Gold mineralization also occurs in intrusive and volcanic rocks adjacent to faults and shear zones.

The Haile gold deposits occur within a 5 km long by 1.5 km wide ENE-trending structural corridor. Northwest-dipping ore zones dip 30 to 500NW and include the Champion, Small, Mill Zone, Chase, Ledbetter, Red Hill and Snake deposits. Both northwest- and southeast-dipping ore zones occur in the Palomino and Horseshoe deposits along the southeast edge of the district. ENE-striking, 40-600NW-dipping faults focus high-grade zones > 3 g/t Au.

Mineralisation and Alteration

Haile gold mineralization occurs as an en-echelon 5 km long by 1.5 km wide cluster of ........

The Haile is currently being mined as an open pit mine. Economic mineralization extends below and outside of the pit extents. Mineralization is concentrated in two main zones based on vertical position which form a “horseshoe” geometry over a vertical distance of 350 m. Both zones strike NE adjacent to the siltstone-dacite contact, however, the upper zone dips about 400NW and the lower zone is nearvertical. The upper zone NW-dipping high-grade lenses of mineralization are focused along beddingparallel foliation with intense silicification. The Horseshoe fault (NE strike, 400NW dip) juxtaposes the hanging wall of upper Horseshoe against barren dacite with a sill-like geometry. This geometry extends southwestward into the nearby Snake pit. The steeply dipping Lower Zone is adjacent to the subvertical contact with barren dacite. This mineralization will be mined as an underground mine and is referred to as Horseshoe.

Based on the orientation, depth, and geotechnical characteristics of the mineralization, a transverse sublevel open stoping method (longhole) with has been selected. The stopes will be 20 m wide and stope length will vary based on mineralization grade and geotechnical considerations. A spacing of 25 m between levels is used. Cemented rock fill (CRF) will be used to backfill the stopes. There will be an opportunity for some non-cemented waste rock to be used in select stopes based on the mining sequence. The CRF will have sufficient strength to allow for ........

A relatively compact Run of Mine (ROM) area is provided for storage and re-handling of ore allowing blending to minimize variation of head grade (sulfur and gold) and rock type, into the crusher. Ore is rehandled into the crusher dump pocket by Front End Loader (FEL).

Ore is reclaimed by an apron feeder onto a vibrating grizzly that delivers scalped oversize to the primary jaw crusher to reduce the ore size from RoM to minus 100 mm. Crushed ore is conveyed for surge and storage of the recombined grizzly undersize fines and primary crushed ore in a coarse ore surge bin or diverted on to an open conical emergency stockpile for later reclaim by Front End Loader (FEL) into a reclaim bin.

Ore is reclaimed from either the surge or reclaim bins, separately or simultaneously, using apron feeders onto a SAG mill feed conveyor belt delivering into the SAG mill feed chute.

Ore is milled in the SAG–Ball Mill-Pebble Crusher (SABC) circuit. The SAG mill operates in closed circuit with a vibrating discharge screen and a pebble return circuit incorporating a surge bin and Sandvik CH-440 cone crusher. The ball mill operates in closed circuit with hydrocyclones to produce the desired grinding product size of 75 microns.

Selected flotation reagents are added in the grinding circuit. A portion of the grinding circuit ball mill circulating load is treated in a flash flotation cell with the concentrate going to the regrind circuit. The grinding circuit product passes to a bank of bulk rougher flotation cells to recover the balance of the sulfide mineralization. Thereafter, the combined flash and rougher flotation concentrates are reground in a two-stage circuit utilizing an ETM-1500 tower mill in closed circuit with cyclones to a P80 under 40 microns and then followed by an M10000 Isamill in closed circuit with cyclones to a target P80 of 13 microns.

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