Gold mineralization in the district is best characterized as low-sulfidation epithermal with the precious metal mineralization associated both with sulphidation of iron in the host rocks and the precipitation in veins of quartz and/or carbonate controlled by boiling. Silica-adularia alteration is intimately associated with the disseminated mineralization and is an important form of ground preparation for later vein forming events.

Mineralization at the NBP is typical of other low-sulfidation type gold systems in, and around, the Walker Lane trend, such as: Bullfrog, Round Mountain, Rawhide, Aurora, Bodie and Comstock. These deposits commonly contain higher grade gold in vein mineralization surrounded by zones of lower grade disseminated mineralization which is the accepted exploration model at NBP.

Two styles of precious metal epithermal mineralization are present at the NBP: 1) high grade, structurally controlled fissure veins and associated stockwork zones, and 2) low-grade disseminated or replacement deposits within altered volcanic rocks.

The 2016 report assumes conventional surface mining methods using surface drill and blast techniques with off highway haul trucks and front end loaders.

Mining production would come from open pit mining methods. As this is an assessment that is preliminary in nature, unsmoothed Whittle pits were used as the basis of the open pit production quantities.

In the conceptual mine plan, 10 meter high benches would be drilled and blasted, then loaded into 136 tonne haul trucks using 13 cubic meter front end loaders. Haul trucks would deliver the mineralized material to either the mill crushing system or a conveyor/stacker to place the blasted material on a leach pad.

The method chosen for gold recovery for the disseminated mineralization in the Sierra Blanca/Savage Valley, Mayflower, and Jolly Jane material evaluated in this report is a standard heap leach recovery circuit commonly used in the region. The higher grade YellowJacket Josh Vein and stockwork material would be processed through a small gold milling / gravity / cyanide leach circuit.

Due to the apparent effect of particle size on gold recovery, the heap leach assessment was based on a feed size P80 -76mm (3 inches) produced from ultra-high intensity blasting, eliminating the need for crushing. This material would also be suitable for loading onto a conveyor and pad stacking system for delivering the mineralization to the heap leach pad.

The cyanide solutions from the heap leach would be treated in a Carbon-in-Columns (CIC) gold adsorption circuit, while the mill circuit would utilize Carbon-in-Leach (CIL) for gold recovery from the milled slurry. Carbon from the CIC and CIL circuits would be processed in one carbon handling circuit located at the mill. The carbon handling would include carbon stripping, acid washing, and reactivation circuits. The process would produce a doré bar for shipping to a refinery for final metal processing.

The gold recovery and reagent consumptions for the heap leach materials are based on +100 bottle roll tests at varying sizes and 40 column tests, and are described in Section 13 of this report. In the test program Savage Valley ores were independently tested. Because of the metallurgical response, similar geology and overlapping location of the two pits, the Savage Valley and Sierra Blanca ores were combined and described hereafter as Sierra Blanca.

The higher grade YellowJacket material would be processed using a small mill / gravity / cyanide leach circuit. The material would be stage crushed through tertiary crushing, followed by primary ball milling, gravity separation of the cyclone underflow, CIL leaching of the gravity tail (cyclone overflow), carbon stripping/acid washing/regenereation, and dore production.

The North Bullfrog heap leach materials would be conveyed to the heap leach pad at a nominal rate of 41,400 tonnes per day. The mineralized material would be stacked on the heap in 30’ lifts. Lime would be added to the material stream on the heap leach feed conveyor belt. The heap would be leached using buried emitters with a weak cyanide solution. The leachate solution would be treated in 6-stage carbon columns.

ROM mineralized material would be ultra-fine blasted and delivered from the mine by haul truck and direct dumped into a hopper connected to the heap leach feed conveyor. A feeder would transfer the heap leach feed to a conveyor/stacker system.

The CIC Plant would consist of six-5.5 m (18 feet) cascading carbon columns processing approximately 30,300 l/m (8,000 gpm) ofsolution.

The mill feed material would be delivered from the mine via haul truck and dumped onto a concrete pad housing a variable rate feeder. Milling would be performed using a single stage primary ball mill in closed circuit with cyclones.

The gravity circuit would consist of a single centrifugal type gravity separation unit (Knelson or Falcon type). The concentrate from the gravity concentrator would be flushed from the concentrator and pumped to the refinery for high intensity cyanide leaching.

The mill product, cyclone overflow, would flow by gravity to a trash screen and the first of two leach tanks. The leach tanks would provide for approximately 24 hours of leach time. After leaching, the slurry would flow to the first of six Carbon in Leach (CIL) tanks. Stripped carbon would be added to the circuit in the last CIL tank and would be pumped once a day upstream into the fifth CIL tank. Loaded carbon would be taken from the first CIL tank, for processing in the carbon handling circuit, where it would be screened, stripped of gold, acid washed, and regenerated in a reactivation kiln prior to being brought back to the sixth tank.

The refinery would have electrowinning cells with sludge tanks, a mercury retort, flux mixer and furnace. The refinery would also contain the high intensity leach circuit for the gravity concentrate. Pregnant solutions from the high intensity leach would be combined with the pregnant strip solution from the strip circuit and would be processed in one of two electrowinning cells. Periodically, the electrowinng cells would be drained, cathodic sludge would be pressure washed from the cathodes, and the sludge would be drained from the cell and placed into a mercury retort for mercury removal.