The Goldstrike deposits are all Carlin type deposits, with fine to very finely disseminated gold and arsenic bearing pyrite. The host rocks are generally sedimentary, mostly calcareous formations, frequently altered and decalcified. There is hydrothermal alteration and there are collapse structures which generated the breccias that host the deposits. The alteration and folding and faulting have led to poor rock quality in the deposits in generally and locally very poor ground conditions in the vicinity of the major faults.

The Meikle deposit, formerly known as the Purple Vein, is located approximately 1.5 mi north-north-west of Barrick’s Betze-Post deposit and is currently in production. The deposit is approximately 800 ft to 2,000 ft below the surface.

Hydrothermal and collapse breccias in the Bootstrap Limestone member of the Roberts Mountains Formation, and to a lesser extent, the Popovich Formation are the dominant host for gold mineralization at Meikle. Breccia geometries are complex, with multiple breccia types observed. Mineralization is predominantly hosted in a breccia derived from a zone of dolomitic alteration that mantles the Bootstrap Limestone. Dolomite and other carbonate rich rocks occurring within the host breccia have been completely digested and replaced by silica. The gold enriched pyrite is disseminated throughout the siliceous breccia host. A rhyodacite dike, which pre-dates mineralization, also occurs in the Main Zone.

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Underground mine production comes from the Meikle's underground zones:
West Banshee, East Banshee, Meikle Main, Meikle Extension, South Meikle, Griffin, West Griffin.

The Meikle production shaft is approximately 548.6 m (1,800 ft) deep, extending to the 1,128 m (3,700 ft) level.

Goldstrike underground operations use two mining methods for extraction: long hole open stoping and underhand drift & fill, both of which rely on cemented backfill for support.

In relatively good to fair ground conditions, where longhole stoping methods are used, the wall and back instability is reduced by mining smaller, longhole sections and filling before mining the next section. In poor ground, the underhand drift and fill method provides a backfill roof for subsequent lifts in the mining cycle.

Transverse longhole stopes are designed at various heights ranging from 35 ft to 100 ft, based on the existing and planned sill development levels used in the active mining areas. Stope widths are designed at 20 ft to 25 ft, based on the ground conditions. In secondary stopes, the width is dictated by the actual dimensions of the adjacent primary stopes. Development of the secondary sills may be reduced to 13 ft leaving a rock “skin” to account for poor quality backfill in the adjacent stopes. The overall stope length is based on the transverse dimension of the ore, however, individual stopes can be limited to 45 ft. Transverse longhole stopes are designed ........

Goldstrike process facilities provide the capability to treat single refractory ore (sulphidic) and double refractory ore (sulphidic and carbonaceous) through roasting or pressure oxidation. The roaster circuit accommodates Goldstrike open-pit and underground ore as well as Cortez Hills Open Pit (CHOP) and Cortez Hills Underground (CHUG) ore. A blended feed to the roaster is required to control the circuit heat balance. Pressure oxidation also receives a blended feed from stockpiles and operates as either alkaline or acid POX dependent upon feed carbonate/sulphide ratios. Pressure oxidation is followed by CaTS leaching, also referred to as the Thiosulphate Leach Conversion (TLC) with an RIL adsorption circuit for gold recovery. Respective facilities include:

1. An autoclave circuit consisting of:
• Primary crushing
• Two parallel SAG Mill-Ball Mill grinding circuits with pebble crushing
• Five parallel autoclaves capable of alkaline or acid POX
• Two par ........