Geological characterization to identify upgrade potential and enhance mining efficiency

Upgrade via screening is a cost-effective way to remove un-economic material early in the mining value chain (MVC). Screening can reduce the amount of material sent for further size reduction and thus reduce the overall amount of energy and water used in the MVC. Exploitation of preferential grade deportment by size (PGDS) is used by this upgrade method as it takes advantage of the propensity for some ores to exhibit preferential breakage which lead to concentration of valuable mineral phases in finer size fractions. Geological parameters linked to PGSD have been identified through drill core-based detailed logging and data collection using manual (e.g. rebound hardness, portable XRF, magnetic susceptibility) and bench-scale (semi)-automated tools (e.g. hyperspectral mineralogy, down-hole XRF) and include mineralization texture and paragenesis as well as degree of alteration. Knowledge of detailed deportment of valuable phases was obtained from a rapid, low-resolution LA-ICP-MS technique developed by CODES Analytical laboratories. The geological parameters were compared to upgrade potential as measured by Response Ranking (RR), a method developed by CRC ORE to allow comparison of upgrade potential via screening within and between mineral deposits. Case study samples from porphyry copper vein and disseminated ores show clear differences in RR with vein-related mineralization showing a higher upgrade potential. Samples from intrusion-related gold deposits show that vein paragenesis, vein volume, abundance and spacing, and alteration style and intensity can be significant with respect to RR. Preliminary machine learning-based models demonstrate that geological and geochemical features can be used to effectively model RR and estimate upgrade potential, thus allowing it to be mapped and included in 3D models. The use of geological characterization data from drill core allows upgrade potential to be identified early and permits its use in deposit evaluation, mine design and planning