Geometallurgy

Geometallurgy is:
* the geologically informed selection of a number of test samples to determine metallurgical parameters and
* the distribution of these parameters through an orebody using an accepted geostatistical technique to support metallurgical process modelling.

The distribution can be influenced by the geological structure of the ore body, in that the lithology can have an effect on some of the parameters. Geometallurgy quantifies the variability of the ore deposit in terms of process parameters such as ore hardness, flotation kinetics and leach kinetics. The data is then applied to the deposit block model or the mine plan, typically through use of geostatistics. After this, geometallurgically enabled mathematical models,for grinding and flotation are used to generate economic parameters such as throughput, grind size, grade and recovery and return these to the block model. The models currently available, Flotation Economic Evaluation Tool, and Comminution Economic Evaluation Tool are capable of handling large data sets in an operational secure environment.

Geometallurgy complements, but does not replace, the traditional metallurgical approach during the development and operation of a mine. Geometallurgical information is used to:
• inform flowsheet design
• size equipment
• assist in plant design
• optimize plant and mine to plant performance
• forecast production
• reduce risk during feasibility, preproduction and operation.

THE BENEFITS OF GEOMETALLURGY

Geometallurgy significantly reduces the impact of spatial uncertainty in mine planning because it documents the variability in a deposit. This lowers project risk by enabling:
• rigorous documentation of geological and mineralogical impact on metallurgical performance and grindability
• plant design that recognizes the inherent variability of the deposit
• forecasting of production parameters such as plant throughput, grade, recovery, P80 and concentrate grade on a quarterly or yearly basis, with a statistical confidence interval
• optimization of plant performance with respect to ore variability
• effective mining of the ore over the entire mine life
• optimized mine resource and plant performance

"WHAT PROJECTS BENEFIT MOST FROM A GEOMETALLURGICAL APPROACH?"

Geometallurgy is used to characterize ore variability during any stage of exploration, development or operation. It is well suited to:
• Highly variable or strongly zoned deposits
• Several close deposits that will be milled together
• Remote or deep deposits that are readily drilled but not easily bulk sampled
• Projects requiring complex or new metallurgical approaches
• Brownfields or sight-of-mine exploration and expansion projects that exploit new, deeper or adjacent reserves
• Projects with significant legacy drill core that are being reevaluated due to new economic circumstances

THE COMPONENTS OF GEOMETALLURGY

Geometallurgy consists of several component activities including:
* Sampling
* Variability testwork, using standardized, low-cost tests that require a small sample volume
* Related data collection and correlations
* Addition of data into block model or mine plan
* Geostatistical data handling
* Process modeling