Alteration and mineral assemblages throughout the deposit are represented by widespread argillic alteration, generally abundant alunite, and the presence of minor amounts of base metals, all of which indicate the ore deposits to belong to the high sulfidation (acid sulfate) class of epithermal mineral deposits. Fluid inclusion data indicates the solutions that deposited the coarse-grained quartz were dilute, with a salinity of 1-2 weight percent NaCl and temperatures ranging 200 to 300° C. Temporal relationships and the thickness of the tuff units suggest that the depth of formation was more than 900m. The geometry of the deposit is controlled by two dominant geologic features; favorable stratigraphic horizon, and structural connectivity to mineralizing fluids. In high sulfidation environments the fluids ascend via structural feeders and under acid attack particularly replaces more favorable units; in the case of Isabella Pearl the Guild Mine member of the Mickey pass Tuff was this unit.

The gold-silver mineralized zones include the Isabella, Pearl, and Civit Cat oxide deposits and the Pearl and Civit Cat sulfide deposits, collectively referred to in this report as the Isabella Pearl deposit. Alteration and mineral assemblages at Isabella Pearl, including widespread argillic alteration and generally abundant alunite, indicate the deposits belong to the high-sulfidation class of epithermal mineral deposits. K-Ar age determinations indicate the mineralization is abou ........

The Isabella Pearl mine design consists of one main pit and several smaller sub-pits accessing the Isabella, Pearl and Civit Cat North deposits. Open pit mining is conducted by conventional diesel-powered equipment, utilizing a combination of blasthole drills, wheel loaders, and 91-tonne (100-short ton) trucks to define, and handle ore and waste. Support equipment includes graders, track dozers, and water trucks. Higher-grade ore (>0.61 g/t Au) is hauled to the crushing area and crushed before being placed on the leach pad. Low-grade ore between 0.33 and 0.61 g/t Au is hauled directly to the low-grade stockpile. Waste rock is stored in the waste rock facility located near the pit to reduce haulage costs.

The final pit was designed using 6 m (20 ft) benches with a bench face angle of 68°, and an inter-ramp slope of 49.7° between a triple bench-catch of 8 m (26 ft). Haul roads were designed to 14 m (46 ft) widths for one-way traffic and 24 m (79 ft) widths for two-way traffic. These widths included an external safety berm in compliance with Mine Safety and Health Administration (MSHA) regulations. The final location of the ramps was optimized to reduce the overall waste stripping in areas where the pit slope was required to be less than 50°.

Low-grade ROM ore was initially placed on the heap leach pad with only lime addition on pad areas protected by a minimum of four feet of cover over the leach pad liner and collector piping system. Currently, high-grade ........

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