Geometallurgy

GeoMetallurgy is a multidisciplinary, applied science with the objective of integrating data and practices from the Geosciences (Geochemistry, Geology, Mineralogy and Geostatistics), Sampling, Extractive Metallurgy and Engineering to mitigate risk such that mining outcomes do not fall short of unrealistic technical and financial targets that have historically plagued the industry.

 

If used well ahead of pre-feasibility and feasibility steps in mine planning, quantitative mineralogy coupled with exploration geochemistry can assist in improved sampling and provide early warning of characteristics indicative of ‘poor’ or ‘bad’ ore. Some of these characteristics may be: (1) A very fine grain size distribution of valuable minerals and difficulty in liberation and upgrading despite a high grade, or (2) The presence of an accompanying mineral (or several) that interferes with processing when grain size characteristics are favorable for a given process. Natural variations can be unpredictable and interdependent and capturing this data is essential to reduce risk. Many other natural variations in mineralogy, mineral textures (directly analogous to micro-structure in physical metallurgy) and physical attributes can influence both processing and the interpretation of geochemical variability and of bore-core or composite samples. 

 

In contrast to Process Mineralogy, an Exploration sampling protocol is typically designed around a limited number of replicate polished sections, and on coarsely ground material derived from a conventional ‘assay reject’ size sample (typically 95% passing 2 mm.) Numbers of sections analysed are a function of particle size, fundamental error (complexity of material) and the grade of mineral of interest. For a cost-effective protocol, samples are typically stage-ground to a finer particle size (e.g. passing 600 microns) to reduce sampling and fundamental error and improve counting statistics. Further sample fractionation may be desirable based on the application.

 

Without due diligence and attention to appropriate sampling protocols, poor agreement between mineralogical and geochemical data may result. As a result, clients are encouraged to discuss their needs and expectations for value-added mineralogical services as applied to Exploration. In consultation with us, methods and protocols can be tailored to meet their needs. Development of the sample protocol is held in strictest confidence and quality controls and metrics are established according to agreed upon and rigorous guidelines, using agreement plots as a fundamental quality control tool.