Gold mining companies use FEI's Automated Mineralogy Solutions to quantify the proportion of recoverable gold versus refractory gold (not recoverable) in precious metal ores. This is done by analyzing samples from different stages in the mining process, from in-situ ore (before mining), to feed ore and concentrates (mining & processing), and finally tailings (disposal). From this analysis, gold producers are able to understand the behavior of metal-bearing particles, and thereby improve and optimize the metal's recovery. So, no matter what the recovery process - gravity, magnetic, flotation, roasting, bio-oxidation or pressure oxidation - gold processing plants can be monitored and audited.

A key aspect to Automated Mineralogy is that quantitative data are generated for gold grain sizes, associations and composition, on a sample-by-sample basis. In low grade samples, customized measurement protocols allow for the rapid searching of gold grains, followed by the automated identification of all phases contained within the particle of interest, and finally the ability to relocate and manually investigate all grains and particles found. In a typical analysis, a gold producer might scan 2 million particles daily in order to gain a statistically relevant daily data set on their mine performance.

The main challenge that faces platinum, palladium and rhodium (Platinum Group Metals, or PGM) producers is how to economically concentrate these very valuable minerals when they only occur in trace amounts (<1%), and as grains typically 5-15 microns in diameter, or less. Fortunately, the PGM often coexist with nickel and iron sulphide minerals that are more common (1-5%), have a larger grain size (10-100 microns), and are highly amenable to a process known as froth flotation. So a clear understanding of how sulphides occur within PGM ores is essential. For those PGMs that display a preference for silicates instead of a sulphides, (and in some cases this can be significant), an alternative or modified concentration method needs to be implemented.

Automated Mineralogy enables PGM producers to understand how variations in mineralogy over time impact production Samples taken from grinding circuits and the flotation cells, can be analyzed by Automated Mineralogy techniques, and provide valuable insights into liberation and flotation performance as a function of: particle type, power input and reagent regime. These key input parameters allow the metallurgist to make adjustments to the concentrator so that grade and recovery of the PGM can be optimized.