399 Before presenting the Block Geometallurgical Model as proposed in this paper, we will review the traditional geometallurgical method, based on metallurgical tests from composites. In traditional modelling methodology, geologists first divide the deposit into Geological Units or GUs and obtain “representative” composites of each GU for metallurgical tests to define the respective GMUs or Geometallurgical Units (Figure 3). The main criticism of this method is related to representativeness of the composites, which according to the TOS: Theory of Sampling (Gy 1992, 1999) only become specimens, no samples, because they are obtained through selective procedures, which are not permitted under the TOS. This error is compounded when results of metallurgical tests, obtained from these composites, are boldly and recklessly extrapolated to millions of tons (GMUs), giving rise to the well-known errors traditionally associated with this methodology, which appear when the ore is being processed in industrial circuits. On the other hand, some traditional metallurgical tests like Bond Work Index (BWI), Sag Power Index (SPI), or similar, cannot be incorporated into a probabilistic database, mainly because they are based on specimens and not on systematically obtained samples. Additionally, their acquisition is both very expensive and time consuming (Canchaya 2012 and Canchaya et al. 2013). 5. IMPLEMENTATION OF THE GEO-METALLURGICAL BLOCK MODEL (GMBM) Metallurgists understand “modelling” in a different way to geologists. Metallurgical modelling aims to find a deterministic relationship between input variables (mainly mineralogical) and output variables (mainly metallurgical); which are usually performed testing Figure 3 – The traditional Geometallurgical Method: From Geological Units (GUs) to Geometallurgical Units (GMUs) through metallurgical tests of composites.
RkJQdWJsaXNoZXIy MTM0Mzk2