The mineralogical and textural characteristics of copper-gold deposits related to mineral processing attributes

The successful liberation of a mineral from its host rock is influenced by the methods of crushing and grinding as well as variability in flotation parameters, all of which are controlled by the mineralogy and textures present in the host rock itself. While it is well known that the mineralogy and texture of a rock influence mineral processing behaviour, previous studies in this field are descriptive, categorical and typically linked to a genetic connotation. In contrast to this, the parameters extracted from physical rock tests are numerical and quantified in a way that can be integrated into a working block model on site. In order to link these two fields together a more quantified approach towards mineralogy and texture is required. In this thesis, a method for the quantified measurement and characterisation of mineralogical and textural attributes that can be used to predict variability in mineral processing behaviours in copper (Cu)-gold (Au) deposits is presented. The styles of mineralisation selected for the method development of this project were a porphyry Cu-Au deposit (Cadia East, NSW, Australia) and iron oxide-Cu-Au (IOCG; Ernest Henry, QLD, Australia) deposit. The method development sites were selected based on variable mineralogical and textural characteristics, both of which made them more amenable to different measurement techniques used within this research. Currently there are limited methods for the routine analysis and characterisation of mineralogical and textural attributes prior to the commencement of mining with the purpose of predicting variability in mineral processing behaviours. Recent advances in the field of microscopy linked with increased computer processing capabilities mean that mineralogical and textural parameters can now be quantified more readily. This project investigated the use of advanced microscopy techniques, high resolution digital images and image analysis as tools for quantifying mineralogical and textural attributes at different scales.