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Mineral resource of the month: beryllium
Beryllium metal is lighter than aluminum and stiffer than steel. These and other properties, including its strength, dimensional stability, thermal properties and reflectivity, make it useful for aerospace and defense applications, such as satellite and space-vehicle structural components. Beryllium’s nuclear properties, combined with its low density, make it useful as a neutron reflector and moderator in nuclear reactors. Because it is transparent to most X rays, beryllium is used as X-ray windows in medical, industrial and analytical equipment.
Mineral resource of the month: nickel
Together with chromium, nickel makes steel more resistant to corrosion. Stainless steel thus accounts for more than 65 percent of primary nickel consumption in the world. One of the more common grades of stainless steel is Type 304, which contains 18 to 20 percent chromium and 10.5 to 12 percent nickel. Owing to their high corrosion resistance, nickel-bearing stainless steels are widely used in the transportation sector, the energy sector, the food preparation and processing industry, the beverage industry, the pharmaceutical industry and the medical community.
Mineral resource of the month: barite
Also called barytes, barite forms in various geologic environments and is frequently found with both metallic and nonmetallic minerals. Most barite is produced by open-pit mining techniques, and most crude barite requires some upgrading to meet minimum purity or specific gravity levels.
Mineral of the month: tungsten
Tungsten has the highest melting point of all metals, one of the highest densities and, when combined with carbon, is almost as hard as diamond. These and other properties make it useful in a wide variety of important commercial, industrial and military applications.
Mineral resource of the month: vanadium
Vanadium, the name of which comes from Vanadis, a goddess in Scandinavian mythology, is one of the most important ferrous metals. Vanadium has many uses, but the metal’s metallurgical applications, such as an alloying element in iron and steel, account for more than 85 percent of U.S. consumption. The dominant nonmetallurgical use of the metal is as a catalyst for the production of maleic anhydride and sulfuric acid, ceramics, vanadium chemicals and electronics.
Mineral resource of the month: soda ash
Soda ash, also known as sodium carbonate, is an alkali chemical that can be refined from the mineral trona and from sodium carbonate-bearing brines. Several chemical processes exist for manufacturing synthetic soda ash.
Mineral resource of the month: sulfur
Since domestic sulfur production peaked at nearly 11 million metric tons in 1974, the sulfur industry has undergone dramatic change. In 1974, mined sulfur produced using the Frasch hot water method provided 8 million tons of sulfur, representing 75 percent of total elemental sulfur production. (In the Frasch process, hot water is injected directly into the sulfur-containing mineral strata, melting the crystalline sulfur, which then lifts to the surface with air.) The remaining 25 percent was produced as byproduct sulfur.
Mineral resource of the month: molybdenum
Molybdenum is a metallic element that is most frequently used in alloy and stainless steels, which together represent the single largest market for molybdenum. Molybdenum has also proven invaluable in carbon steel, cast iron and superalloys. Its alloying versatility is unmatched because its addition enhances material performance under high-stress conditions in expanded temperature ranges and in highly corrosive environments. The metal is also used in catalysts, other chemicals, lubricants and many other applications.
Mineral resource of the month: perlite
Perlite is found in most homes, workplaces and schools. Most of the white ceiling tiles in offices and classrooms are made primarily of perlite. The soil around potted plants also has small white grains of perlite. Other than in these lightweight construction products and horticultural soil mixes, perlite is used in food processing for filtration and in natural gas processing as a low-temperature insulation that aids the gas liquefaction process. Perlite is also an excellent high temperature insulator and resists burning.
Mineral resource of the month: fluorspar
Fluorspar, this month’s featured mineral resource commodity, has been widely used in steelmaking since the introduction of basic open-hearth furnace technology in the late 19th century. Its uses have grown and changed over the last 100 years, and now fluorspar’s most important markets are fluorochemicals, aluminum refining and steel. M. Michael Miller, Fluorspar Commodity Specialist for the U.S. Geological Survey, has prepared the following information about fluorspar.
Mineral resource of the month: lead
The United States is a major producer and consumer of refined lead, representing almost one quarter of total world production and consumption. Two mines in Alaska and six in Missouri accounted for 97 percent of domestic lead production in 2002. The United States also imports enough refined lead to satisfy almost 20 percent of domestic consumption. Other major producers or consumers of refined lead in the world are Australia, Canada, China, France, Germany, Italy, Japan and the United Kingdom.
Mineral resource of the month: rare earths
As if classified as a top-secret project, the rare earths have been shrouded in secrecy. The principal ore mineral of the group, bastnäsite, rarely appears in the leading mineralogy texts. The long names of the rare-earth elements and some unusual arrangements of letters, many Scandinavian in origin, may have intimidated even those skilled in phonics. Somewhat obscurely labeled, the rare earths are neither rare nor earths (the historical term for oxides). They are a relatively abundant group of metallic elements that occur in nature as nonmetallic compounds and have hundreds of commercial applications.
Mineral resource of the month: tantalum
Tantalum is a metal that is critical to the United States because of its defense-related applications in aircraft, missiles and radio communications. It is ductile, easily fabricated, highly resistant to corrosion by acids, a good conductor of heat and electricity, and has a high melting point. Tantalum’s first commercial usage was as filament material in incandescent electric lamps in the early 1900s.
Mineral resource of the month: copper
Beryllium metal is lighter than aluminum and stiffer than steel. These and other properties, including its strength, dimensional stability, thermal properties and reflectivity, make it useful for aerospace and defense applications, such as satellite and space-vehicle structural components. Beryllium’s nuclear properties, combined with its low density, make it useful as a neutron reflector and moderator in nuclear reactors. Because it is transparent to most X rays, beryllium is used as X-ray windows in medical, industrial and analytical equipment.