Moganite
Moganite is a silicate mineral with the chemical formula SiO2 (silicon dioxide) that was discovered in 1984.[1] It is made up of covalent bonds and has a lattice structure, also known as a monoclinic crystal system. Moganite is considered a polymorph of quartz because it has the same chemical composition but a different chemical structure.[2]
As of 1994, the International Mineralogical Association (IMA) had disapproved it as being a separate species because it was not clearly distinguishable from quartz.[3] It has only recently been approved as a valid species by the CNMNC, the Commission on New Minerals, Nomenclature and Classification (part of the IMA).[4]
This mineral is “virtually indistinguishable” from a rock called chalcedony that is made up of both moganite itself and quartz. It has been mainly found in dry locales such as Gran Canaria and Lake Magadi.[5] It is even named for a municipality of Gran Canaria called Mogán.[6] Physically, it has a hardness of about 6, a dull luster and appears gray in color but transparent.
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Moganite with Chalcedone from Barranco de Los Medios Almudes. Analyzed Sample (Ian T. Graham, Australian Museum pers. comm ). Size is 5.5x4 cm. Collected 2003.[7]
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Moganite intimately intergrown with quartz (chalcedony). Arme Hilfe Mine, Ullersreuth, Thuringia, Germany. Sample size 1 mm, analyzed material. Collection and foto Thomas Witzke.[8]
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Moganite intimately intergrown with quartz (chalcedony). Ehrenfriedersdorf, Erzgebirge, Saxony, Germany. Sample size 5.6 cm, analyzed material. Collection and foto Thomas Witzke.[9]
- ^ Ralph, Jolyon, and Ida Ralph. "Moganite: Moganite Mineral Information and Data." MinDat. 2007. Aug. 2007 <http://www.mindat.org/min-2739.html>.
- ^ "Glossary of Rock and Mineral Terms - P." Inland Lapidary. 24 July 2007. Aug. 2007 <http://www.inlandlapidary.com/user_area/glossaryP.asp>.
- ^ Origlieri, Marcus. "Moganite: a New Mineral -- Not!" Lithosphere (1994). Aug. 2007 <http://fgms.home.att.net/moganite.htm>.
- ^ Nickel, Ernest H., and Monte C. Nichols. "IMA/CNMNC List of Mineral Names." Materials Data. June 2007. Aug. 2007 <http://www.geo.vu.nl/users/ima-cnmmn/MINERALlist.pdf>.
- ^ Heaney, Peter J., and Jeffrey E. Post. "The Widespread Distribution of a Novel Silica Polymorph in Microcrystalline Quartz Varieties." Science ns 255 (1992): 441-443. JSTOR. Aug. 2007. Keyword: moganite.
- ^ "Moganite Mineral Data." Web Mineral. Aug. 2007 <http://webmineral.com/data/Moganite.shtml>.
- ^ Graham, Ian T. Moganite with Chalcedone From Barranco De Los Medios Almudes. 2003. Mogán, Gran Canaria. Moganite. Aug. 2007 <http://www.mindat.org/photo-83097.html>.
- ^ Witzke, Thomas. Moganite Intimately Intergrown with Quartz (Chalcedony). Arme Hilfe Mine, Ullersreuth, Thuringia, Germany. MINERAL FOTO ATLAS. Aug. 2007 <http://tw.strahlen.org/fotoatlas1/moganite_foto.html>.
- ^ Witzke, Thomas. Moganite Intimately Intergrown with Quartz (Chalcedony). Ehrenfriedersdorf, Erzgebirge, Saxony, Germany. MINERAL FOTO ATLAS. Aug. 2007 <http://tw.strahlen.org/fotoatlas1/moganite_foto.html>.