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Name: Guyanaite RRUFF ID: R070444 Ideal Chemistry: CrO(OH) Locality: Merume river, Kamakusa, Mazaruni District, Guyana Source: Michael Scott S104672 [view label] Owner: RRUFF Description: Black alluvial grains, a mixture of guyanaite, bracewellite, eskolaite and quartz, colloquially known as merumite Status: The identification of this mineral has been confirmed only by X-ray diffraction |
RAMAN SPECTRUM | ||||||||||||
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BROAD SCAN WITH SPECTRAL ARTIFACTS | ||||||||||||
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POWDER DIFFRACTION | |||||||
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RRUFF ID: | R070444.1 | ||||||
Sample Description: | Powder, mixture includes bracewellite, eskolaite and quartz | ||||||
Cell Refinement Output: |
a: 4.8773Å b: 4.3111Å c: 2.9547Å alpha: 90° beta: 90° gamma: 90° Volume: 62.127Å3 Crystal System: orthorhombic |
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REFERENCES for Guyanaite | |
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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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Christensen N, Hansen P, Lehmann M S (1976) Isotope effects in the bonds of β-CrOOH and β-CrOOD, Journal of Solid State Chemistry, 19, 299-304 |
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Milton C, Appleman D E, Appleman M H, Chao E C T, Cuttita F, Dinnin J I, Dwornik E J, Ingram B L, Rose H J (1976) Merumite, a complex assemblage of chromium minerals from Guyana, U.S. Geological Survey Professional Paper, 887, 1-29 [view file] |
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Fleischer M, Cabri L J, Nickel E H, Pabst A (1977) New mineral names, American Mineralogist, 62, 593-600 [view file] |
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Jahn S, Wunder B, Koch-Müller M, Tarrieu L, Pöhle M, Watenphul A, Taran M N (2012) Pressure-induced hydrogen bond symmetrisation in guyanaite, β-CrOOH: evidence from spectroscopy and ab initio simulations, European Journal of Mineralogy, 24, 839-850 |
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Schultze D J, Flemming R L, Shepherd P H M, Helmstaedt H (2014) Mantle-derived guyanaite in a Cr-omphacite xenolith from Moses Rock diatreme, Utah, American Mineralogist, 99, 1277-1283 |
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