commercialization. Under this criterion, a block is considered ore while its net value is positive and waste when it fails to cover those costs. This approach establishes an economic threshold that defines the inclusion of material in the mine plan and conditions the pit design, mining sequence, and final reserve estimation. ● Cut-off based on direct cost versus recovered metal value, expressed in %Cu or Cu-eq. ● Cut-off based on NSR, Net Smelter Return, which incorporates recoveries, prices, penalties, and smelting charges. 3.4 Pit Optimization and Final Reserve Calculation Once the cut-off grade is defined, optimization is performed using algorithms such as Lerchs–Grossmann, maximum flow, or pseudo-flow. This process determines the optimal pit that maximizes economic value, the final design with phases and ramps, and the mineable reserves, which include only blocks within the pit above cut-off grade, classified as Measured or Indicated and adjusted for dilution and losses. Figure 2 - Current Reserve Estimation Methodology Source: Own elaboration 4. OPTIMIZATION The traditional methodology for quantifying reserves presents limitations due to the application of a fixed cut-off grade, the absence of early preconcentration, and the requirement to process all material without prior selection. This excludes marginal blocks containing recoverable metal, as the cost per tonne exceeds their economic value. Additionally, the lack of differentiation between valuable material and waste generates an operational burden in both mining and processing, increasing energy consumption, costs, and metallurgical losses. Pit designs and tonne–grade curves become constrained by a rigid cut-off that does not reflect mineralogical variability, gangue density, or metallurgical response. In this context, ore sorting technology emerges as an alternative that directly addresses these limitations through the early classification of ore based on physical or chemical properties detectable by sensors, such as XRT, XRF, NIR, among others. Its main
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