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magnetite
magnetite (loadstone, lodestone) An important rock-forming iron oxide Fe2+Fe3+2O4 (FeO.Fe2O3) and member of the spinel group of minerals; belongs to the magnetite series along with magnesioferrite (MgFe3+2O4), franklinite, jacobsite (MnFe3+2O4), and trevorite (NiFe3+2O4); sp. gr. 5.2 (to 4.6); hardness 5.5–6.5; cubic; normally iron-black with a blue tarnish; black streak; sub-metallic lustre; crystals often octahedral and rhombdodecahedral, but it is also massive and granular; cleavage poor, octahedral; strongly magnetic; found extensively in magmatic rocks associated with basic rocks, in pegmatites, in contact metasomatic zones (especially in limestones in regionally metamorphosed rocks due to the dehydration of iron hydroxides), and also in black sands associated with gold gravels.
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AILSA ALLABY and MICHAEL ALLABY. "magnetite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "magnetite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-magnetite.html AILSA ALLABY and MICHAEL ALLABY. "magnetite." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-magnetite.html |
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magnetite
magnetite , lustrous black, magnetic mineral, Fe 3 O 4 . It occurs in crystals of the cubic system, in masses, and as a loose sand. It is one of the important ores of iron (magnetic iron ore) and is a common constituent of igneous and metamorphic rocks. It is found in Norway, Sweden, the Urals, and various parts of the United States. A variety of magnetite, lodestone (or loadstone) exhibits polarity and is especially interesting for its natural magnetism; Magnet Cove, Ark., became famous as a source. |
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"magnetite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "magnetite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-magnetit.html "magnetite." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-magnetit.html |
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magnetite
magnetite Iron oxide mineral (Fe3O4). It is a valuable iron ore, found in igneous and metamorphic rocks. It is black, metallic and brittle. Permanently magnetized deposits are called lodestone. Hardness 6; r.d. 5.2.
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"magnetite." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "magnetite." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-magnetite.html "magnetite." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-magnetite.html |
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magnetite
mag·net·ite / ˈmagnəˌtīt/ • n. a gray-black magnetic mineral that consists of an oxide of iron and is an important form of iron ore. |
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"magnetite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "magnetite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-magnetite.html "magnetite." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-magnetite.html |
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magnetite
magnetite •calcite • campsite
•website • dacite • insight
•Monophysite • magnesite • eyesight
•hindsight • bombsight • foresight
•bauxite • quartzite • leucocyte
•Hussite • gunsight • phagocyte
•marcasite • parasite • anthracite
•oversight • worksite
•bipartite, multipartite, partite, quadripartite, sexpartite, tripartite
•transvestite • airtight • Hittite
•magnetite • appetite • stalactite
•watertight • Levite • Muscovite
•Hepplewhite • bobwhite
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"magnetite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "magnetite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-magnetite.html "magnetite." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-magnetite.html |
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