The mineralized vein at Los Ricos South, which is up to approximately 30 m wide, has had at least three quartz vein formation and metal precipitation events (Nebocat, 2004). The vein strikes across the Property for 3.5 km, following a northwest-southeast trending fault, and dips approximately 65° to 70° to the west.

The chief gangue mineral is quartz, but whereas crystalline quartz is plentiful and colourless, cream colored, milky or occasionally even amethyst, the bulk of the quartz is a dense fine-grained grey, yellowish of greenish porcelain quartz intermixed with chalcedonic quartz of a slightly later origin. This quartz is associated with less grey, brown and white calcite. Some of the calcite was deposited contemporaneously with the quartz, but most of it post-dates the latter. The contemporaneous calcite is more abundant in the vein near surface than at depth. Comb quartz and open vugs in the quartz vein were more abundant in the upper workings near surface. Siderite, rhodochrosite and adularia were also noted as rare occurrences, whereas kaolinite was also present near secondary enriched oxidized mineralized materials. Chlorite and possibly epidote were also in evident in association with the quartz, or in partially replaced rock fragments.

The chief sulphide minerals are galena, chalcopyrite, sphalerite, pyrite, covellite, bornite and silver sulphides. The higher-grade sulphide zones are generally associated with finegrained galena and minu ........

The Los Ricos South Project will consist of both open pit and underground mining operations. Underground mining will generally follow open pit mining, although there will be an overlap of three years. The entire duration of mining activity will be 11 years.

OPEN PIT MINING
The Los Ricos South Property contains several gold vein systems, some of which were partially mined in the past. The deposits are near surface and lend themselves to conventional open pit mining methods. For this PEA production plan, three different open pits will be developed over the life of the Project to support the processing operation.

The topography across the Project site is quite hilly and mining will generally occur in pits located along various hillsides.

The excavation of the open pits will require the removal of three different materials, all of which are tracked separately in the production schedule.
• Overburden: consists of loose material overlying some of the deposits, which will be stripped and hauled to nearby waste rock storage facilities.
• Waste Rock: is barren or low grade material, also placed into nearby waste rock storage facilities.
• Process Plant Feed: is mineralized material above cut-off grade that will be hauled to the process plant facility.

The design of the open pit layouts and the mining schedule requires several steps. These are: 1. Run pit optimizations to select the optimal pit shells to be ........

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The process plant flowsheet design comprises conventional crushing, a semi-autogenous mill with a pebble crusher, and a closed circuit ball mill circuit with cyclones to ensure product (P80) size feed to the leaching circuit. The classified material will be thickened in a pre-leach thickener to increase the slurry density and decrease the slurry volume. The thickener underflow will be filtered in belt filters and repulped with SART discharge solution prior to entering the leach tankage. The thickener overflow water will be recirculated to feed the grinding circuit. After the required leaching retention time, the discharge slurry (and loaded solution) will be filtered in pressure filters. The reason for this is twofold – wash and recover pregnant solution for recovery within the Merrill Crowe system, and also produce “dry” stackable tailings that is less than 16% moisture and less than 2 ppm cyanide in the pore water. At the Los Ricos site, water recovery and management are very impor ........