Mineral processing

Accessory minerals in rocks, ores and mine tailings can represent valuable, but in many cases unrecognized resources for the minerals industry (notably platinum-group minerals (PGM), native gold, silver, diamonds and other rare minerals). In addition, they can also provide unique opportunities for scientific research.

The new technique for the concentration of "heavy" minerals (here meaning minerals with density higher than that of the host rock) from ores, rocks and tailings uses a combination of electric-pulse disaggregation (EPD) for crushing of geological/mineral samples and concentration of comminuted heavy minerals by means of a hydroseparator (HS).

Electric-pulse disaggregation yields a perfect separation of the mineral constituents, since the crushing occurs primarily along grain boundaries and fractures in the sample (boundaries between domains with different physical properties). The technique largely preserves crystals and mineral grains of the sample providing a unique possibility of observing the crystal shape, morphology, primary grain sizes and internal texture of individual mineral grains. Furthermore, alteration products are effectively removed from mineral surfaces producing unusually clean mineral grains. In cases, where mineral associations contain important information for the accessory minerals, the crushing is done by careful use of a shatter box instead of by EPD.

The extraction of "heavy" minerals is done by using a hydroseparator with practically no loss of mineral grains. In different tests, mineral concentrates had 100 to 10,000 times the original proportions of the desired minerals. The technique has been applied successfully to samples having as low as 0.1-1.0 ppm of the phase forming elements of the desired minerals. The technique has been tested on many types of samples which are difficult to separate using normal techniques, and some examples include:


The proposed technique makes it possible to:

Applications of technique