Modern mining is an industry that involves the exploration for and removal of minerals from the earth, economically and with minimum damage to the environment. Mining is important because minerals are major sources of energy as well as materials such as fertilizers and steel. Mining is necessary for nations to have adequate and dependable supplies of minerals and materials to meet their economic and defense needs at acceptable environmental, energy, and economic costs. Some of the nonfuel minerals mined, such as stone, which is a nonmetallic or industrial mineral, can be used directly from the earth. Metallic minerals, which are also nonfuel minerals, conversely, are usually combined in nature with other materials as ores. These ores must be treated, generally with chemicals or heat to produce the metal of interest. Most bauxite ore, for example, is converted to aluminum oxide, which is used to make aluminum metal via...