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Encyclopedia of Global Resources part 77

Encyclopedia of Global Resources part 77 provides a wide variety of perspectives on both traditional and more recent views of Earth's resources. It serves as a bridge connecting the domains of resource exploitation, environmentalism, geology, and biology, and it explains their interrelationships in terms that students and other nonspecialists can understand. The articles in this set are extremely diverse, with articles covering soil, fisheries, forests, aluminum, the Industrial Revolution, the U.S. Department of the Interior, the hydrologic cycle, glass, and placer mineral deposits. . | 708 Magnesium Global Resources The Bushveld intrusion accounts for almost 50 percent of the world s production of vanadium. Stephen C. Hildreth Jr Further Reading Best Myron G. Igneous and Metamorphic Petrology. 2d ed. Malden Mass. Blackwell 2003. Brown Michael and Tracy Rushmer eds. Evolution and Differentiation of the Continental Crust. New York Cambridge University Press 2006. Evans Anthony M. Ore Geology and Industrial Minerals An Introduction. 3d ed. Boston Blackwell Scientific Publications 1993. Naldrett AnthonyJ. Magmatics Sulfide Deposits GGeology Geochemistry and Exploration. Berlin Springer 2004. Schmincke Hans-Ulrich. Magma. In Volcanism. New York Springer 2004. Young Davis A. Mind over Magma The Story of Igneous Petrology. Princeton N.J. Princeton University Press 2003. Web Site U.S. Geological Survey Magma Lava Lava Flows Lave Lakes http vulcan.wr.usgs.gov Glossary LavaFlows description_lava_flows.html See also Earth s crust Igneous processes rocks and mineral deposits Ophiolites Pegmatites Plutonic rocks and mineral deposits Vanadium Volcanoes. Magnesium Category Mineral and other nonliving resources Where Found Magnesium is a widespread and abundant element. Magnesium chloride and magnesium sulfate are present in dissolved form in seawater and underground brines these sources accounted for 43 percent of U.S. magnesium compound production in 2008. Magnesium is also found in many minerals notably magnesite MgCO3 dolomite CaMg CO3 2 and brucite Mg OH 2 . China Russia Israel Kazakhstan Canada and Brazil are among the main producers. For a number of years the United States has withheld its magnesium production statistics to avoid disclosure of companies proprietary data. Primary Uses Magnesium is used principally in alloys refractor y materials 60 percent of U.S. use paper fertilizer chemicals and pyrotechnics. As a compound it can be used as an additive to food in medicine and as a sedative. Technical Definition Magnesium abbreviated Mg atomic number 12