The Property is located within the Western Cordillera of the Andes Mountains and the regional geology is dominated by Cretaceous aged Machay Group limestones and Tertiary aged Pocobamba continental sedimentary rocks, which are referred to as the Casapalca Red Beds. These groups have been deformed by the Huaron anticline, the dominant structural feature of the local area. The limestones and sedimentary rocks are strongly folded and intruded by quartz monzonite and quartz monzonite dikes with associated fracturing. Following the intrusion of the dikes, the sedimentary rocks were further compressed and fractured, and subsequently altered and mineralized by hydrothermal fluids forming the Huaron deposit on the Property. The main lithology in the area of Huaron is a sequence of continental redbeds of the Casapalca Formation which unconformably overlie massive marine limestones. A series of andesites and dacites outcrop to the west of the mine. North-south trending sub-vertical porphyritic quartz monzonite dykes crosscut the mine stratigraphy. Thinly bedded marls and sandstones known as the lower redbeds are present in the central part of the mine and at lower elevations. The upper redbeds are present on the eastern side of the mine, and are comprised of calcareous chert overlying sandstone and marls, in turn overlying the Barnabe quartzite conglomerate at the base of the sequence. On the western side of the mine, the stratigraphy consists of a series of interbedded conglomerates ........

Mining is undertaken using a combination of mechanized cut and fill (C&F) and mechanized sub-level open stoping (SLOS) methods. Sub level open stoping Longitudinal SLOS uses electric hydraulic long hole drills, scoop trams and development waste for backfill. Cement is occasionally added to the waste rock backfill to create a pillar which is stable upon exposure. The dimensions of the mining blocks are based on mining levels, stope layouts, previously experience and geotechnical constraints. Stopes are typically 40 m long but can range between 20 m to 100 m in length. Sub levels spacing varies between 10 m to 12 m apart vertically. Sub levels, cross cuts, drifts, and ramps are excavated at 3.5 m wide by 3.8 m high in sub level stoping areas. More than 80% of the mine’s production is extracted using the long hole stoping method. SLOS is done at Huaron using this methodology and at times by leaving rib pillars and stopping to fill a mined block when access from the mined side of the stope is not available for backfilling. The minimum mining width for SLOS is 1.0 m and planned dilution is included in the mine design. Dilution estimates vary according to the ground conditions, mining method, vein width and the dip of the vein. The dilution factors range from 9% to 36% for planned dilution (LOM average is approximately 24%) and unplanned floor dilution is 7%. In the SLOS areas, dilution is reconciled using a cavity monitoring survey and comparing actual to design. This methodol ........

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