![]() ![]() Radium is usually obtained (with barium impurities) in residues from the production of uranium. It is recovered as the bromide by an involved chemical process. The small amount of the element present in any ore and the difficulty of extraction make it expensive. Radium also is a dangerous material prolonged exposure to even small amounts may cause cancer, anemia, or other disorders. Other radioisotopes (e.g., cobalt-60) are often used in its place when they are less expensive, more powerful, or safer to use. Radium was discovered in 1898 by Pierre and Marie Curie in pitchblende given them by Austria after the uranium salts had been removed for use in glass manufacture. They had earlier found polonium in a similar sample. Metallic radium was isolated by electrolysis in 1910 by Marie Curie and André Debierne they first formed a mercury-radium amalgam by electrolysis and then removed the mercury by distillation. The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2022, Columbia University Press. ![]() All rights reserved.In 1922, a bank teller named Grace Fryer became concerned when her teeth began to loosen and fall out for no discernible reason. ![]() Her troubles were compounded when her jaw became swollen and inflamed, so she sought the assistance of a doctor in diagnosing the inexplicable symptoms. Neodymium, when alloyed with iron and boron, produces the strongest permanent magnets known to exist.Using a primitive X-ray machine, the physician discovered serious bone decay, the likes of which he had never seen. While neodymium's chief use was as a reddish-purple pigment for glass and ceramics, it has other applications in cryocoolers and as a fertilizer. The current reserves of neodymium are believed to be around eight million tons, with around seven thousand tons produced each year. There are an additional twenty-nine radioactive isotopes of neodymium, but the most stable are the two that are found naturally occurring. Two of neodymium's radioactive isotopes, Nd-144 and Nd-150, are also found in nature. The most abundant of these stable isotopes is Nd-142 at a concentration of almost thirty percent of neodymium available. There are five naturally occurring stable isotopes of neodymium. Neodymium is one of the more reactive of the rare earth metals, so it quickly begins to oxidize in air. Neodymium's concentration is about thirty-eight milligrams per kilogram in the crust, which is second only to cerium for abundance of the rare earth elements.Īs a lanthanide, neodymium is present in mischmetal, a naturally occurring conglomerate made up of several lanthanides at varying concentrations. It is most often found as a component in monazite and bastnasite minerals. He had been studying the residue isolated by Mosander several years before when he made the discovery of both elements by fractional crystallization.ĭespite being a rare earth element and never being found in its free form in nature, neodymium is as prevalent in the Earth's crust as nickel, copper, and cobalt. It is a bright silver member of the rare earth metals and a member of the lanthanides group.Īustrian scientist Carl Gustav von Weisbach discovered neodymium at the same time that he discovered praseodymium. Neodymium (Nd) has an atomic number of sixty, and that same number of protons in the nucleus of one of its atoms. ![]()
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