Molybdenite 465064 222852748 2008-07-01T12:49:29Z TXiKiBoT 3171782 robot Adding: [[eu:Molibdenita]] {{Infobox mineral | name = Molybdenite | category = | boxwidth = | boxbgcolor = | image = Molybdenite.jpg | imagesize = | caption = | formula = [[molybdenum]] [[sulfide]]:MoS<sub>2</sub> | molweight = | color = Black, lead-silvery gray | habit = Thin, platy hexagonal crystals terminated by pinacoidal faces, also as tapering six-sided pyramids that can be truncated by the pinacoids. Also massive, lamellar and in small grains in sulfide ore bodies | system = [[Hexagonal]]; 6/m 2/m 2/m | twinning = | cleavage = [0001] Perfect | fracture = flaky | mohs = 1 - 1.5 | luster = Metallic | refractive = Opaque | opticalprop = | birefringence = | pleochroism = | streak = bluish - gray | gravity = 4.73 | density = | melt = | fusibility = Infusible | diagnostic = | solubility = | diaphaneity = | other = Thin cleavage sheets and crystals are flexible, but not elastic. It has a greasy feel and leaves marks on fingers }} '''Molybdenite''' is a mineral of [[molybdenum disulfide]], [[molybdenum|Mo]][[sulfur|S]]<sub><small>2</small></sub>. Similar in appearance and feel to [[graphite]], molybdenite has a lubricating effect that is a consequence of its layered structure. The atomic structure consists of a sheet of molybdenum atoms sandwiched between sheets of [[sulfide]] atoms. The Mo-S bonds are strong, but the interaction between the sulfur atoms at the top and bottom of separate sandwich-like tri-layers is weak, resulting in easy slippage as well as [[cleavage plane]]s. Associated minerals include [[pyrite]], [[chalcopyrite]], [[quartz]], [[anhydrite]], [[fluorite]], and [[scheelite]]. Occurs in high temperature [[hydrothermal]] [[ore]] deposits. Important deposits include the disseminated porphyry molybdenum deposit at [[Questa, New Mexico]] and [[Climax, Colorado]]. Molybdenite also occurs in [[porphyry copper]] deposits of [[Arizona]], [[Colorado]], [[Utah]], and [[Mexico]]. The element [[rhenium]] is always present in molybdenite as a substitute for molybdenum usually in the parts per million (ppm) range, but often up to 1-2%. High rhenium content results in a structural variety detectable by [[X-ray diffraction]] techniques. Molybdenite ores are essentially the only source for rhenium. The presence of the [[radioactive isotope]] rhenium-187 and its daughter isotope [[osmium]]-187 provides a useful [[geochronology|geochronologic]] dating technique. == References and external links == {{commonscat|Molybdenite}} *Dana's Manual of Mineralogy ISBN 0-471-03288-3 *[http://mineral.galleries.com/minerals/sulfides/molybden/molybden.htm Mineralgalleries.com] *[http://webmineral.com/data/Molybdenite.shtml Webmineral] *[http://www.mindat.org/min-2746.html Mindat.org] *[http://www.cnr.colostate.edu/airie/Molybdenite.htm Molybdenite Dating] [[Category:Sulfide minerals]] [[Category:Molybdenum minerals]] [[Category:Lubricants]] [[ca:Molibdenita]] [[de:Molybdänglanz]] [[eu:Molibdenita]] [[fr:Molybdénite]] [[it:Molibdenite]] [[lt:Molibdenitas]] [[hu:Molibdenit]] [[nl:Molybdeniet]] [[ja:輝水鉛鉱]] [[pl:Molibdenit]] [[pt:Molibdenite]] [[ru:Молибденит]] [[sk:Molybdenit]] [[fi:Molybdeenihohde]] [[uk:Молібденіт]]