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Name: Weddellite RRUFF ID: R110123 Ideal Chemistry: Ca(C2O4)·2H2O Locality: Tucson, Arizona, USA Source: Gordie Downs Owner: RRUFF Description: White to colorless spheroidal crystals found in the pith of a living Saguaro cactus Status: The identification of this mineral has been confirmed by single-crystal X-ray diffraction. |
Mineral Group: [ Oxalate (13) ] | ||
Quick search: [ All Weddellite samples (2) ] |
RAMAN SPECTRUM | ||||||||||||
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BROAD SCAN WITH SPECTRAL ARTIFACTS | ||||||||||||
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POWDER DIFFRACTION | |||||||
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RRUFF ID: | R110123.9 | ||||||
Sample Description: | Single crystal, powder profile is calculated | ||||||
Cell Refinement Output: |
a: 12.410(4)Å b: 12.410(4)Å c: 7.386(3)Å alpha: 90° beta: 90° gamma: 90° Volume: 1137.5(2)Å3 Crystal System: tetragonal |
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REFERENCES for Weddellite | |
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American Mineralogist Crystal Structure Database Record: [view record] |
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Anthony J W, Bideaux R A, Bladh K W, and Nichols M C (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America. [view file] |
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Bannister F A, Hey M H (1936) Report on some crystalline components of the Weddell Sea deposits, Discovery Reports, 13, 60-69 [view file] |
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Frondel C, Prien E L (1942) Carbonate-apatite and hydroxyl-apatite in urinary calculi, Science, 95, 431-431 |
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Sterling C (1965) Crystal-structure analysis of weddellite, CaC2O4·(2+x)H2O, Acta Crystallographica, 18, 917-921 |
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Tazzoli V, Domeneghetti C (1980) The crystal structures of whewellite and weddellite: re-examination and comparison, American Mineralogist, 65, 327-334 [view file] |
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Mandarino J A, Witt N V (1983) Weddellite from Biggs, Oregon, U.S.A., The Canadian Mineralogist, 21, 503-508 [view file] |
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Mandarino J A (1983) Weddellite from Lutterworth Township, Haliburton County, Ontario, The Canadian Mineralogist, 21, 509-511 [view file] |
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Frost R L, Weier M L (2003) Raman spectroscopy of natural oxalates at 298 and 77 K, Journal of Raman Spectroscopy, 34, 776-785 [link] |
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Frost R L, Weier M L (2003) Thermal treatment of weddellite--a Raman and infrared emission spectroscopic study, Thermochimica Acta, 406, 221-232 |
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Garvie L A J (2003) Decay-induced biomineralization of the saguaro cactus (Carnegiea gigantea), American Mineralogist, 88, 1879-1888 [view file] |
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Echigo T, Kimata M, Kyono A, Shimizu M, Hatta T (2005) Re-investigation of the crystal structure of whewellite [Ca(C2O4)·H2O] and the dehydration mechanism of caoxite [Ca(C2O4)·3H2O], Mineralogical Magazine, 69, 77-88 [view file] |
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Hernanz A, Gavira-Vallejo J M, Ruiz-Lopez J F (2007) Calcium oxalates and prehistoric paintings. The usefulness of these biominerals, Journal of Optoelectronics and Advanced Materials, 9, 512-521 |
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Echigo T, Kimata M (2010) Crystal chemistry and genesis of organic minerals: A review of oxalate and polycyclic aromatic hydrocarbon minerals, The Canadian Mineralogist, 48, 1329-1358 [view file] |
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Izatulina A, Gurzhiy V, Frank-Kamenetskaya O (2014) Weddellite from renal stones: Structure refinement and dependence of crystal chemical features on H2O content, American Mineralogist, 99, 2-7 |
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Sturm E V, Frank-Kamenetskaya O, Vlasov D, Zelenskaya M, Sazanova K, Rusakov A, Kniep R (2015) Crystallization of calcium oxalate hydrates by interaction of calcite marble with fungus aspergillus niger, American Mineralogist, 100, 2559-2565 |
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Mills S J, Christy A G (2016) The Great Barrier Reef Expedition 1928–29: The crystal structure and occurrence of weddellite, ideally CaC2O4·2.5H2O, from the Low Isles, Queensland, Mineralogical Magazine, 80, 399-406 |
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Piro O E, Baran E J (2018) Crystal chemistry of organic minerals-salts of organic acids: the synthetic approach, Crystallography Reviews, 24, 149-175 |
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