لخّصلي

The extraction of metals from the earth is an ancient process, but also one that has seen numerous improvements in the most recent two centuries.But virtually all of the elemental metals that have been discovered in the past 300 years have been found either alloyed with another element or elements, or have been found as some kind of ore, often an oxide or sulfide ore or both.The techniques used to separate metals from such ores have become very well-established, mature processes, and none are considered dependent on any biotechnological steps.

The extraction of metals from the earth is an ancient process, but also one that has seen numerous improvements in the most recent two centuries. Some metals exist in nature in what is called their reduced state. Gold, silver, copper, and iron are examples of this which have been known since ancient times. But virtually all of the elemental metals that have been discovered in the past 300 years have been found either alloyed with another element or elements, or have been found as some kind of ore, often an oxide or sulfide ore or both. The techniques used to separate metals from such ores have become very well-established, mature processes, and none are considered dependent on any biotechnological steps. In the past few deca- des, however, there have been enormous inroads made into the metals industry whereby a biotechnological step is used in some way during metals beneficiation, extraction, or purification often called bioleaching. Such steps generally repre- sent an improvement in any process, since most metal refining chemistry involves producing stoichiometric or greater amounts of one or more unwanted byproducts, often a pollutant.