Biomining is the use of microorganisms in the recovery of metals from
ores. During bioleaching, metals such as copper, nickel or zinc are
oxidized through microbial action from the water-insoluble sulfide to
the soluble sulfate forms. Although gold is inert to microbial action,
microbes can also be used in gold recovery from certain types of ores
because as they oxidize the ore, they open up its structure, thereby
allowing a gold-solubilizing agent such as cyanide to penetrate the ore.
The book describes several industrial bioleaching and biooxidation
processes as well as the underlying theory and biology of the microbes
involved.