Geometallurgical Confidence

The quantification of mining resources seeks to progressively increase the knowledge and geological confidence of a deposit. On the other hand, the quantification of reserves applies various modifying factors that affect extraction and require the multidisciplinary contribution of mining, metallurgy, processes, communities and the environment, etc.

In geometallurgy, criteria of quantity of samples and type of metallurgical research are used according to the mineral; the number of samples is aligned with the complexity of the deposit and the tonnage to be processed. A natural refinement of this practice is to apply concepts like those used in resource and reserve categorization.

Geometallurgical confidence is a tool that allows optimizing the efforts of sampling, characterization and quantification of the risk associated with aspects of processing, investment, and operational costs, among others. This categorization is constructed based on the variability of the attribute under study (recoveries, concentrate grades, etc.), the sampling scheme and number of samples estimating each block; Furthermore, the quality of the metallurgical projection model also comes into play. In this way, it is possible to link metallurgy to the level of risk accepted by the owners in relation to a project under analysis (how to build this categorization tool will be addressed in future articles).

Geometallurgical confidence can be implemented in a traffic light approach to facilitate communication of results to project stakeholders (red, yellow and green for low, medium and high confidence). For example, for the first 3 years of a project at the end of its feasibility stage, categorization may require over 70% of the mining plan in high confidence and less than 30% in medium confidence. This aligns, for example, with the investment estimate that may require +/- 25% certainty.