Mineral Processing Methods

Digging ore from the earth is only half the battle. Often just as challenging and costly is the processing of the ore, which takes place in mills, smelters and refineries.

While the interior of a mill seems, to the visitor, to be a baffling maze of tanks, pipes, pumps, conveyors, motors, chemicals, pulps and solutions, this seeming confusion is actually a carefully designed system constructed for one objective — to recover the valuable minerals locked up in the ore.

The end product from a mill is called a concentrate, or in the case of gold and silver, a doré bar of the metal itself,

All milling and concentrating processes begin with a crushing and grinding stage, which usually represents most of the total cost of processing the ore.

Ore minerals are usually found within and among grains of other ore minerals or (relatively) worth less gangue minerals, This fact makes the processing of some ores more complicated than others.

For instance, a complex sulphide ore containing microscopic particles of sphalerite within small blebs of galena or other sulphides presents a special challenge to the metallurgical engineer, that is, to design a milling process that will liberate these various constituents from each other as cleanly and economically as possible so that each may be recovered.