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Introduction Nickel alloys have been used since centuries for making coins, jewelry, and household utensils due to their hardness and relatively high oxidation resistance. Despite the wide spread of nickel minerals, the silvery-white metal was first recognized as a new element in 1751, when the Swedish mineralogist Axel Frederik Cronstedt discovered in niccolite an impure form of nickel. The name nickel originates from kupfernickel, a German name for niccolite, a copper-red color mineral containing B44% nickel and 56% arsenic. . | Nickel E Cattaneo and B Riegel GmbH Co. KG Brilon Germany 2009 Elsevier B.V. All rights reserved. Introduction Nickel alloys have been used since centuries for making coins jewelry and household utensils due to their hardness and relatively high oxidation resistance. Despite the wide spread of nickel minerals the silvery-white metal was first recognized as a new element in 1751 when the Swedish mineralogist Axel Frederik Cronstedt discovered in niccolite an impure form of nickel. The name nickel originates from kupfernickel a German name for niccolite a copper-red color mineral containing 44 nickel and 56 arsenic. General Properties About 0.016 of the earth s crust is composed of nickel occuring as five stable isotopes. Ni-58 67.8 Ni-60 26.2 Ni-62 3.7 Ni-61 1.3 Ni-64 1.2 The atomic number of nickel is 28 with the electron configuration Ar 3d84s2. Nickel has two allotropic crystal structures 1 the closed-packed hexagonal a phase and 2 the face-centered cubic ß phase with a density of 8908 g cm 3 and a melting point of 1453 C. Ferromagnetism is one of the outstanding physical properties of nickel Tc 358-363 C also observed for the other transition metals of Group VIII iron Tc 770 C and cobalt Tc 1131 C . Mineral Deposits The world s largest deposits are found in Russia 18 Canada and Cuba 17 each and New Caledonia in the South Pacific 13 . Significant deposits of sulfide ores are found in Norilsk-Talnakh in Siberia and in Ontario Sudburry district in Canada. Other well-known ores are in the Kola Peninsula Petschenga and Montschegorsk and the Urals Tscheljabinsk Jekaterinburg Orenburg in Russia. Nickel deposits are also situated in Indonesia Guatemala and Australia. Extraction and Processing Nickel ores consist of sulfides arsenides and oxides. The choice of the extraction process for nickel depends on the mineral type - more than 60 of the world nickel production derives from sulfidic Ni-Fe-Cu ores and the most important mineral is pentlandite Fe Ni 9S8. Although the
