Metallic resources form an integral part of the raw materials that fuel our modern economic society.
For example, gold is used not only in the fabrication of ingots and jewelry, but also in dentistry and in the construction of scientific instruments and other electronic equipment. Although there are many actively mined ore deposits distributed world wide, active mineral exploration is necessary to maintain a constant supply of copper and gold, as well as zinc and other metals. On a seemingly disparate note, the search for alternate energy sources is a global endeavor, and geothermal resources represent one way to reduce global fossil fuel consumption. In geothermal fields, present day reservoirs of hot water, some of which may have zones of economic or subeconomic mineralization forming within them at depths of hundreds to thousands of meters, may be mined for their heat by pumping water from the reservoir to the surface, extracting the heat, and reinjecting the spent fluid back into the Earth's subsurface. These include elements such as K, Rb, Na, F, Pb, Zn, Sn, W, Mo, U, Th, Bi, Nb, Ta and other metals.