Mineralization in the Filo del Sol area shows affinities with both porphyry copper-gold-molybdenum and high- sulphidation gold-silver epithermal systems. The deposit defined by the mineral resource is best classified as epithermal in the north (Filo del Sol) and copper-gold porphyry plus epithermal in the south (Tamberias). The mineralized system in its entirety is thought to represent a porphyry – epithermal system, with multiple intrusive and breccia centres, and so combines aspects of both these deposit types. The Flamenco fault is an important structure that separates the exposed porphyry Au-Cu system in the south at Cerro Vicuña - Tamberias, from the relatively down-dropped block to the north with the preserved high-sulphidation system at Filo del Sol.

The Filo del Sol deposit encompasses both the Filo del Sol high-sulphidation epithermal system and part of the Tamberias area which is interpreted as a fault-offset part of the same hydrothermal system. The deposit occurs within a porphyry Cu-Au and high-sulphidation epithermal Cu-Au-Ag system that formed during rapid uplift and erosion in the Middle Miocene. Porphyry intrusions and associated Cu-Au mineralization are associated with an early epithermal system have been eroded and overprinted by at least one subsequent stage of porphyry intrusion and epithermal system development. The Filo del Sol system is largely associated with this second, later part of the progressive development of the system.

The Filo del Sol property is characterized by a large hydrothermal alteration zone extending for approximately 18km2, from south of Cerro Vicuña to the Maranceles and Potro areas in the north. The alteration types and zonation across the area allow for a series of porphyry intrusive centres with associated higher-level high-sulphidation epithermal systems that have been structurally-offset and exposed to different depths. Alteration in the south around Cerro Vicuña-Tamberias includes both remnant potassic porphyry-style alteration, with overprinting epithermal alteration; while Filo del Sol up to Maranceles presents high-sulphidation epithermal mineralogy. The system at Ventanas has not yet been extensively evaluated but appears to also host both porphyry and epithermal features.

In the immediate Filo del Sol deposit area, alteration is consistent with a high-sulphidation epithermal system. The deposit occurs within a lithocap domain formed to the south of one of the main up-flow zones mapped through alteration mineralogy. A shallowly west- and north-dipping quartz-alunite alteration domain is controlled, at least in-part, by the basal contact of the conglomeratic rocks. Below the quartz-alunite zone, alteration changes rapidly to argillic assemblages that include illite and downwards into montmorillonite. Immediately overlying the quartz-alunite zone are alteration domains resulting from fluid interactions at a receding paleo-water surface, including a domain of massive silicification, followed upwards generally by residual silica with several perched lenses of opaline silica, and capped by steam-heated alteration formed in the vadose zone above the progressively descending paleo-water surface.

The study contemplates open pit mining methods, with conventional drilling, blasting and loading performed on 12m benches. Autonomous haulage was incorporated to take advantage of the technology’s proven productivity improvements and operating cost savings. The open pit would have a mine life of 14 years, including pre-stripping, with a life of mine strip ratio of 1.5:1. A maximum mining rate of approximately 65 Mt per year (including waste) is required to provide the nominal 60,000 tonnes per day of ore to the process facility. A total of 259 Mt of ore is expected to be processed over the life of the mine.

The process plant for the Filo del Sol project is designed to treat 60,000 tpd of ore through a sequential heap leach process, to produce copper cathodes and gold/silver doré.

Ore will be trucked from the mine and either stockpiled or direct tipped into the primary crusher. The ore will be further crushed through a closed-circuit secondary crushing system to a stockpile.

Crushed ore will be processed at an on/off heap leach pad where the copper will be leached in acid and then recovered from the leach solution by solvent extraction and electrowinning to produce LME grade copper cathodes. Metal leaching is expected to span over 13 years.

Once the copper is leached, the ore will be rinsed, neutralized and removed from the on/off leach pad by a bucket wheel reclaimer. The material will then be agglomerated using cement, and subsequently stacked on a permanent heap leach pad where gold and silver will be leached in a cyanide solution. Gold and silver will be recovered from the pregnant gold leach solution by a Merrill-Crowe zinc precipitation process and then smelted to produce doré.

A portion of the barren leach solution, following zinc precipitation, will be treated to minimize the build-up of recirculating copper in the gold circuit solutions and return free cyanide to the gold heap leach. This treatment is based on the SART process (sulphidization, acidification, recycling and thickening) which produces a copper sulphide precipitate (which grades approximately 65% copper) and recovers cyanide for use in the heap leach.