A new method to quantify mineral textures for geometallurgy

A geometallurgical model was developed in three steps using the Malmberget iron ore deposit, northern Sweden as a case study. It is based on a mineralogical-particle approach which means that the mineral information is in the focus. Firstly, the geological model describes quantitatively the variation within the ore body in modal composition and mineral textures. Traditional geological textural descriptions are qualitative and too vague and therefore a method that describes and distinguishes quantitatively different mineral textures and creates different types called textural archetypes was developed. The second part of the geometallurgical model is a sub-model which forecasts how ore will break and which kind of particles will be generated. A simple algorithm was developed to estimate the liberation distribution for the progenies of each textural archetype. The model enables numerical prediction of the liberation spectrum with varying modal mineralogy. The third step includes a process model describing quantitatively how different particles behave in each unit process stage. As a whole the geometallurgical model takes the spatial information of the geological model in terms of modal composition and textural type. The particle breakage model forecasts the liberation distribution of the corresponding feed to the concentration process and the process model returns the metallurgical response in terms of product quality (grade) and effectively (recovery).