Why are the stochastic pit limits optimized by KPI-COSMO usually larger?
Different aspects contribute to the larger pit limits generated by KPI-COSMO. First, the geostatistical simulations provide a significantly better representation of the spatial distribution of high grades within the mineral deposits. Second, the scheduling of high-grade mining blocks opens up the opportunity to economically extract some low and medium grade blocks throughout the sequence of extraction. Third, the blending high, medium, and low grades across multiple processing destinations of the value chain are also considered by KPI-COSMO instead of pre calculated economic values of blocks. Therefore, the pit limit generated by KPI-COSMO is not only physically different, but also usually larger (around 25%) than the conventional pit limits.