The Nechí Alluvial Project is situated in the alluvial valley and flood plain of the Nechí River lower basin that lies within the foothills of the Central Cordillera of the Andes Mountains.

The Nechí alluvial deposits may be classed as a Tertiary gravel plain gold placer with bordering bench or terrace deposits. The gravel plain style of placer is Mineros’ primary exploration target for dredging. Gravel plain deposits are generally characterized by well-rounded gravels, few boulders, and fine gold distributed vertically and laterally in the pay formations. Such placers are formed in low-velocity shifting stream channels in low-gradient valleys. Gold grades in the Nechí River flood plain are elevated at the mouths of creeks draining the high ground (Segovia batholith) to the east and these areas likely represented the merging of creek or river placers with the main gravel plain. In the upper reaches of the Nechí River, the goldbearing gravel plain placers likely grade into river placers.

Gold in the Nechí alluvial gold deposits consists of free grains that are predominantly No. 4 or smaller. No. 4 grains are very fine (flour or powder gold), with individual grains weighing approximately 0.02 mg. No. 2 and No. 3 gold grains are also present. In terms of grain counting, No. 4, and smaller grains account for 96% of the grains logged in drill hole sampling, however, the weight contribution of No. 3 and No. 4 grains is 86%. As determined from fire assays of bu ........

There are four main mining methods carried out at the Nechí Alluvial Property. The first, and predominant, method is alluvial plain mining using a combination of suction and bucket line dredges. The second method is suction plain mining using new “Brazilian” suction dredges that have on board processing plants. The third method is by the “Llanuras” production unit, which comprises a suction dredge (No. 20) for overburden removal, a modified suction dredge (No. 21) for mining the gold-bearing gravels, and a new floating plant called the “Llanuras Plant”. The fourth method is terrace/old tailings mining using an amphibious excavator.

Dredging operations are carried out 24 hours per day, 365 days per year. At approximately 80% availability due to equipment maintenance and clean-up, actual dredging is effectively 284 days per year. The nominal production capacity of each of five bucket line dredges, used to mine pay gravel, is 500 m3 /h. The nominal capacity of the seven wheel cutter suction dredges used to strip overburden, and modified suction dredge No. 21 to mine pay gravel, ranges from 300 m3 /h to 500 m3 /h. Planned annual production from mid-2021 to 2034 of 26.85 Mm3 results in an average hourly production rate of 4,084 m3 per hour (pay gravel plus overburden). The current mine life is 12.7 years with a combination of large suction and bucket line dredges, smaller alluvial plain wheel cutter (Llanuras production unit) and Brazilian rotary head suction dredges th ........

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