The Vizcachitas mineral deposit has similar characteristics to other Andean-style porphyry copper and molybdenum mineral deposits. This type of mineralized deposit contains large masses of hydrothermally altered rocks, sulphide-bearing small veins, disseminated sulphides, quartz veins and stockworks that may cover several square kilometres. These altered areas are commonly coincident with shallow intrusives, hydrothermal breccias and intrusion breccia.

The mineralized system of Vizcachitas comprises complex porphyries and breccias with copper and molybdenum mineralization, which intrudes andesitic volcanic rocks. The earliest intrusive rocks are porphyries of diorite composition. The petrographic work identifies this unit as a diorite with biotitized mafics (phlogopite) with deformed quartz veins and others of hyaline quartz/anhydrite veins. This is associated with abundant chalcopyrite and development of sericite haloes where the pyrite is greater than chalcopyrite. This phase has the highest primary grades for both copper and molybdenum.

Hydrothermal breccias have various matrix including: siliceous, silica-K feldspar, silica-sericite, silica-anhydrite, silica- sulphides and silica-tourmaline. These are genetically related to each igneous event. The hydrothermal breccias are normally associated with higher copper grades than their related intrusive phase.

The first inter-mineral intrusive phase is of a tonalitic composition and is followed by a later granodiorite intrusive. The petrographic work describes this as a fine granodioritic porphyry with potassic alteration (biotite with anhydrite) and white quartz B veins with abundant potassic feldspar and anhydrite. This is then cut by anhydrite-gypsum veinlets and sulfides.

A phreatomagmatic breccia or diatreme that is post-mineral has cut through the central part of the project. It is composed or fragments of pre-existing igneous and volcanic rocks in a matrix of rock dust and clays. This unit is barren.

Dacitic porphyries dykes are the last intrusive event and cut the phreatomagmatic breccia and are also barren.

The latest mapping carried out by Los Andes Copper shows a vertical zoning that is typical of porphyry type systems. The first 10 m to 70 m thick upper zone is partially leached with some copper sulphides remaining, iron oxide mineralization, jarosite, goethite, and to a lesser extent hematite. copper oxides, such chrysocolla, are occasionally observed in fractures.

Below the leached zone, there is a secondary enrichment zone or supergene zone of weak to moderate intensity, with presence of chalcocite and covellite, which occurs in fractures and as fine surface coatings on pyrite and chalcopyrite. The supergene thickness varies between 2 m and 100 m, with a mean thickness of 50 m, copper grades may exceed 1% and the average grade for the defined Resource Estimate is 0.501% Cu.

Below the secondary enrichment zone, there is the hypogene or primary mineralization. This mineralization is mainly made up of chalcopyrite, with significant amounts of associated pyrite. Bornite occurs in several of the drill holes below 800 m. In the drill hole V2017-10, located at the northern end of project, bornite accounts for 15% of the total sulphides below 900 m. This indicates that a possible bornite core could be located below the current drilling.

There is no correlation between the molybdenum mineralising event and the copper mineralization. The molybdenite is and is normally associated with small type B quartz veins and small late hydrothermal type D veins.

An open pit mining method has been selected for the Vizcachitas deposit mainly owing to the copper and molybdenum grades and the continuous mineralization occurring near the surface, which is a considerable benefit in relation to the waste/mineral ratio for open pit mining.

Previous engineering studies have discarded an underground mining option owing to the lack of grades to support such an option.

The mine has been scheduled to operate 360 days per year. The plan contemplates two 12-hour shifts per day. Mining operations include drilling, blasting, loading, hauling and support services.

The annual operation period defined for the mine considers minimal snow-related downtime. The deposit is located at an average elevation of 2000 masl, with potentially minor snow events. The roads and working areas may be promptly cleared by using support equipment considered in the operation.

Crushing
The mineralized material from the mine will be transported by trucks to the primary crushing facility, where it will be discharged into the bin which feeds a primary gyratory crusher. The crusher will discharge onto an apron feeder and the crushed material will then be transported by a belt conveyor to the covered coarse material stockpile.

Grinding
Semi-Autogenous Grinding (SAG) was selected for the milling stage, as it is efficient for this scale of operation and adds flexibility for future expansions. A SAG circuit has the capacity to be easily doubled by adding one or two ball mills whilst maintaining only one grinding line.

The SAG mill will be fed by a conveyor belt from the coarse material stockpile. The SAG mill discharge slurry will pass through a double deck screen with 13 mm sieve size to remove pebbles. The pebbles will be transported by conveyor belt to the pebble crusher plant and then returned to either the primary SAG mill circuit or the secondary ball mill circuit. The double screen undersize and the ball mill will discharge into a sump pump. The combined product will be pumped to the cyclone cluster. The cyclone underflow will return to the ball mills circuit and the overflow will report by gravity to rougher flotation.

The design of the pebble crusher circuit considered a pebble circulating load of 30% and 20% of the new feed rate for SAG circuit. This is based on industry experience with mineralized material of similar competency.

The ball mill secondary grinding circuit was designed to produce a final product size of P80 at 240 µm.

Copper-Molybdenum Flotation Circuit Design
The flow sheet selected shown in Figure 17.2 consists of rougher flotation, rougher concentrate regrind, three stages of cleaner flotation and three stages of scavenger flotation. The mineralized material will require a fine regrind of the rougher concentrate to a P80 of 45 µm to achieve adequate recovery. After regrinding, conventional flotation will be used to enable the production of commercial grade concentrates.

Rougher concentrate, as well as first and second scavenger concentrate, will report to the regrind cyclone pump box. The regrind cyclones will target an overflow size of P80 at 45 µm, which will be achieved with a cluster of cyclones operating in reverse closed circuit. The cyclones overflow will report to the first cleaner flotation while the underflow will feed the vertical mill. The vertical mill discharge will recirculate back into the cyclone pump box.

The first cleaner stage will be composed of con ........