The gold mineralization at Mesquite Mine was deposited in an epithermal setting, within 500 to 1,000 ft of the surface. The majority of the economically attractive mineralization is found in the biotite gneiss and hornblende-biotite gneiss, while the mafic gneiss and intrusive rocks are generally less mineralized. Gold mineralization is found both disseminated and vein hosted within these units. The majority of the veining is controlled by faults and fault junctions, which have moderate to steep dips.

The gold mineralization dominantly occurs in two types:
- pods of mineralization limited in lateral and vertical extent at fault intersections;
- trends of mineralization along faults.

The principal types of mineralization defined at Mesquite are as follows:
• Early epidote - quartz veinlets overprinted by chlorite veinlets;
• Two-stage siliceous matrix breccia (SMBX) developed along faults planes with quartzadularia matrix ± pyrite;
• Quartz ± adularia ± pyrite ± electrum veinlets with sericite halos;
• Ankerite ± Dolomite ± pyrite veinlets;
• Bleached zones on fault planes with green sericite ± pyrite;

Gold occurs at Mesquite as both submicron disseminated and coarse gold. All documented gold occurrences are native gold, and classification has been based on silver content and grain size. A silver-free native gold is the most common type in the oxidized zone. It occurs in particles less than five microns, altho ........

Mesquite is an operating open pit mine with ore processed by heap leaching using a CIC circuit to recover gold. Current mine production is a nominal 178,000 tons per day of total material, including a nominal 50,000 to 68,000 tons per day of ore that is hauled to the leach pad. Total mine production is capped at 65 million tons per year based on a restriction of the air quality permit.

Highwall slope angle criteria vary by area and pit. In general, the steepest walls are on the south side of the property and the shallowest in the northeast. In general, the inter-ramp angles vary from 29 to 42 degrees depending on pit area and wall orientation.

The final pit designs are based on pit shells using the Lerch-Grossman algorithm in Mine Plan software. Pits were generated using a revenue factor of 1.0 or gold price of $1,350/oz. These pit shells were used as the basis for the final phase designs in each pit area. The pit optimization utilized metallurgical recoveries of 75% for oxide ores and 35% for non-oxide ores.

The detailed pit phase designs at Mesquite are based on the pit optimization shells generated with the current resource model.

Three pit areas are considered in the reserves statement: Brownie (1-phase), Vista East (2-phases), Vista West (1-phase) plus two areas in the Big Chief waste dump. Each pit has been designed to accommodate mining by the existing mining fleet. Mining occurs on 30 ft. lifts with catch benches spaced eve ........

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