A greater understanding of your process by mineralogical ore characterisation

Ore characterisation is a very broad term that is viewed differently by geologists, mineralogists and metallurgists.  It does however fundamentally cover the concept of defining the building blocks of an ore, giving insight into how best to deal with it.

The use of process mineralogy in comprehensive ore characterisation has always been a benchmark application.  The depth of understanding that mineralogy can give us into the fundamental parameters of an ore can be invaluable in devising the most effective method for winning value from it.  The advent of new mineralogical technologies, such as the e-beam based QEMSCAN and MLA, has made this even more accessible, opening up possibilities for comprehensive characterisation of ores at any stage in the mine life cycle.

In my experience with process mineralogy, characterisation of materials can have the greatest impact on process improvement.  This is not restricted to development of new projects but is equally applicable in optimisation of all areas from grade control and estimation to minimising losses to tailings.

In essence ore characterisation can be applied to the following areas in the most traditional sense.

1. Definition of ore types in conjunction with geological setting as an indicator of mineralisation for exploration projects.
2. Ore typing and material definition for development of flowsheet options in new projects.
3. A tool for more effective grade estimation, control and variability analysis during mining.
4. A diagnosis tool for identification of process inefficiencies and fundamental optimisation of metal recovery.
5. An environmental tool for evaluation of waste rock and tailings for storage or clean-up.

The areas through which detailed ore characterisation can be used cover the entire mine life cycle.  It forms the benchmark for all the uses of mineralogy in processing or mining operations because of the fundamental parameters it examines.

Addressing ore characterisation is about more than simply looking at the mineralogy of a representative sample.  A good study will require an understanding of geology, mineralogy and metallurgy.  Integrating all of these disciplines will allow the drivers for ore formation to be established and how they will affect final processing.  Using this approach can be a very powerful tool as the first stage in any evaluation project and it addresses the fundamentals of the problem and draws together all aspects.

Generally, by utilising existing knowledge and smart use of automated mineralogical systems it is possible to generate comprehensive ore characterisation programs that are cost effective and valuable.  Much improved turn-around times can also be achieved, meaning that if characterisation has not been previously performed it is possible to integrate it into a troubleshooting program.

Overall, by using ore characterisation in a smart way there are significant cost savings to be made in many other areas of evaluation.  Effectively, it is possible to target specific areas of the ore behaviour once they are identified, eliminating the need to unfocused metallurgical testwork.  Doing this allows metallurgical work to focus on validating solutions rather than diagnosing problems.

If you have any thoughts or questions about ore characterisation please let us know.  This is a very broad overview and raises more questions than it answers but will provide the springboard for future posts examining each area of characterisation in more depth.