Mineralization in the Gold Bar District has most of the characteristics of Carlin-type gold deposits described in Muntean and Cline (2018), including: carbonate host rocks, tectonic setting, structural and stratigraphic ore controls, hydrothermal alteration consisting of dissolution and silicification of carbonate and argillization of silicates, auriferous arsenian pyrite, a geochemical signature containing Au-As-Hg-Sb-Tl, low Ag (Ag/Au<1), and lack of clear relationship with intrusions. Gold mineralization in the Gold Bar district is localized at the intersections of a complex array of structures with permeable and reactive strata. Carbonate dissolution, argillization of silicates, sulfidation of ferroan minerals and silicification of limestone characterize the alteration assemblage related to the main stage of mineralization. Gold is found as sub-micron inclusions or solid solution in arsenian pyrite. Oxidation has liberated gold from the original pyrite, making it amenable to cyanide leaching. Common trace elements include arsenic, antimony, thallium,and mercury.

Central Nevada is underlain by Paleozoic sedimentary and volcanic rocks which were in turn covered by Tertiary volcanic rocks and sediments. During the early Paleozoic, this part of Nevada was the western pre- continental margin of the North American plate. From Silurian through Devonian time, extensive carbonate platforms developed along the continental margin, generating a thick wedge of carbonate sediments to the west as the basin subsided. Farther to the west in deep water, shale, chert and sandstone (siliciclastic rocks) were deposited during that time.

Within the Gold Bar North (GBN) area, three gold deposits have been defined: Gold Pick, Gold Ridge and Cabin Creek. Mineralization in Gold Pick has a strike length of over 4,000 ft with a width of 1,600 ft and thickness of 100 – 150 ft. Gold Ridge and Cabin Creek are ancillary deposits comprising together approximately 22% of the mineral resource. All defined mineralization lies within 500 ft of surface in oxidized carbonate host rocks.

There are two structural blocks in the district, separated by the regionally extensive RMT. Deep-water shale and chert, known as the Vinini Formation (upper plate) were pushed eastward onto the carbonates (lower plate) along the RMT. Late-Paleozoic clastic sedimentary rocks were deposited on both upper and lower plates. Younger (post-Permian) lowangle faulting locally placed lower plate rocks on top of both the upper and lower plates. Tertiary extension resulted in the complex basin and range high-angle block faulting that defines the range today.

SIGNIFICANT MINERALIZED ZONES
Gold Bar North
The Gold Pick, Gold Ridge and Cabin Creek deposits are found in the McColley Canyon Formation.

Mineralization is controlled both by stratigraphy and by overprinting structures. Much of the mineralization in all three deposits is at an orientation that mimics bedding and probably represents favorable permeability in certain debris flow subunits that were selectively more receptive to gold deposition. At Gold Pick East this bedding orientation is N50°E, 23°SE, at Gold Pick West it is N07°E, 24°E, at Gold Ridge it is N20°E, 20°SE and at Cabin Creek it is N01°E, 27°E.

Mineralization also tracks a strong northeast-southwest fabric that is supported by structures identified during surface mapping. These southwest-trending structures are at moderate to steep angles (45-70°NW). At Gold Pick East, the high-angle structures focus grade along on N245°E, 45-60°NW. At Gold Ridge, the orientation is N265°E, 70°NW. The highest gold grades in the deposit are concentrated along these structures likely at the intersection with low-angle stratiform mineralization.

All of the mineralization found to date at the GBN occurs as sediment-hosted, “Carlin-type” gold deposits. The deposits are hosted in carbonate-rich sedimentary rocks of the Devonian Nevada Formation and are characterized by micronsized gold and a distinct hydrothermal alteration suite.

If the term “Carlin-type gold deposits” is used in its strictest sense, the deposits are restricted to a small part of the North American Cordillera in northern Nevada and northwest Utah. Most such deposits are located along long-lived, deep crustal structures inherited from Late Proterozoic rifting and formation of a passive margin. They are hosted in a Paleozoic miogeoclinal carbonate sequence that is either structurally overlain by a eugeoclinal siliciclastic sequence (the Roberts Mountains Allochthon), or stratigraphically overlain by a miogeoclinal siliciclastic sequence deposited in the resulting foredeep (Overlap Assemblage). Gold mineralization is localized at intersections of a complex array of structures with permeable and reactive strata. Carbonate dissolution, argillization of silicates, sulfidation of ferroan minerals and silicification of limestone characterize alteration related to the main stage of mineralization. Gold is found as micron inclusions or solid solution in arsenian pyrite. Common trace elements are antimony, thallium and mercury.

Gold Bar South
The lower 100-200 ft of the overlying Mississippian Webb Formation (siltstone, mudstone), hosts the bulk of the GBS (Gold Bar South) gold mineralization.

The most economically prospective mineralization at GBS occurs at the crest of an east-tilted doubly plunging anticline, interpreted from consistent Devils Gate – Webb Formation contacts recorded in drill logs. Overall the anticline is tilted, with a steeper 25° dipping east limb and a flat west limb. The anticline plunges north at approximately 10° and plunges steeper to the south at approximately 20° before it is ultimately covered by deep basin-filling alluvium.

Mineralization occurred at the base of the Webb Formation and was subsequently offset by a series of east-side-downstepping northeast and northwest-trending normal faults. Mineralization is rarely preserved along these high-angle faults, though undoubtedly some of them served as conduits to fluid flow during the gold event. Locally, normal faulting has created small grabens, in which the thickness of mineralization appears to be enhanced. There is evidence, by reconstructing grade trends of some left- lateral oblique slip on northeast-trending faults, especially in the southern part of the deposit. Lastly, and similar to Gold Bar North, there appears to be some “ponding” of mineralization in troughs of the Devils Gate – Webb Formation contact. These are interpreted as potential karst dissolution zones or debris flows with enhanced permeability.

Gold mineralization at GBS was deposited in brecciated siltstones of the Webb Formation, at and immediately above its contact with the Devils Gate Limestone. Lesser, but important amounts of mineralization occur in the adjacent Devils Gate Limestone as well. Mineralization in GBS consists of epithermal, disseminated, sediment-hosted gold, in zones related to hydrothermal dissolution in limestone and the resulting collapse breccia in the overlying siliciclastic unit. Gold is associated with brecciated, oxidized, silicified, and argillized mudstones, siltstones, and sandstones of the Webb Formation and is usually accompanied by silicification and strong barite veining. Jasperoid along the trace of the fault is brecciated and contains veins of barite and scattered gold mineralization.

The Gold Bar Project is planned for production using conventional hard rock open pit mining methods. Ore production to the crusher is planned at a maximum capacity of 7,500 tpd (2,750 ktons/yr). Additional run of mine (ROM) material will be placed when available. The maximum ore production to the leach pad (crushed & ROM) is planned to be 8,880 tpd (3,240 ktons/yr). The mine production schedule was developed with the goal of filling the crusher at the required ore rate and maximizing the project return on investment. The total material rate is tied to equipment productivity and fluctuates by period. The maximum total production is expected to reach a rate of 43,000 tons/day (16,100 ktons/yr). The mine is scheduled to operate 6 days/wk with two, 10-hour shifts/day.

The Gold Bar Project is currently being mined by a contractor, and this is planned to continue. Contractor equipment on hand is often variable. There is flexibility in the fleet size, and the actual mining fleet in use will likely vary depending on the contractor’s fleet on hand.The schedule and production requirements were based on the following fleet assumptions: Bench heights are planned at 20-ft; drilling is planned based on using four rotary down-the-hole hammer drills with 45,000 lb pull down capacity and 6.75 in diameter blast holes; and the blasted rock will be loaded into 100-ton haul trucks using three, 16-cubic yard front-end loaders.

The mine plan was developed with a phased approach. The phase designs, mine schedule, and mine equipment requirements are summarized in this section.

Gold Bar is a low-grade, disseminated gold series of deposits with mineralization close to the surface at an average remaining head grade of 0.025 oz/t Au.

The phases were tabulated from the mineral resource block model and those tabulations were used as input to the development of the mine production schedule.

Waste rock will be stored in several waste rock facilities designed in close proximity to each pit to reduce haulage costs. Whenever possible, pit backfilling will be utilized if doing so proves to be economic during operations. Some waste mined late in the mine life will be placed in a designated storage facility to meet closure requirements.

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Gold and silver are extracted from mineralized material by either milling or heap leaching depending on, among other things, the amount of gold and silver contained in the material, whether the material is naturally oxidized or not, and the amenability of the material to treatment.

At the Gold Bar mine, precious metal recovery is through conventional heap leaching and adsorption, desorption, regeneration (ADR) technology for metal extraction from crushed and agglomerated ore.

HEAP LEACH PAD DESIGN
The heap leach pad is designed to be constructed in two phases (Phases 1A and 1B) with 4 cells each, for a total of 8 cells. The leach pad and process facilities extend from an elevation of 6,750 ft amsl at the toe of the process ponds to an elevation of 6,980 ft amsl at the northwestern edge of the leach pad perimeter road. The grade of the lined base receiving ore will range from 7 to 8% on the western half and 2 to 4% on the eastern half. In total, the leach ........