ABSTRACT
At most modern mining operations, whether surface or underground, the ores are not of suffi ciently high grade to ship long distances to smelters, and they are subjected to milling, mineral dressing, or benefi ciation, usually at or near the mine site. All of these terms are sometimes referred to as ore dressing. Ore dressing is the mechanical separation of the grains of ore minerals from the worthless gangue. The resulting concentrate contains most of the ore minerals, and the waste is called tailings. The separation from valuable minerals and worthless gangue requires the following two steps, size reduction (milling and grinding) and separation of ore minerals from gangue materials (concentrating).
