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American Mineralogist, Volume 94, pages 293–302, 2009 0003-004X/09/0203–293$05.00/DOI: 10.2138/am.2009.2957 293 Formation of aragonite mesocrystals and implication for biomineralization Gen-Tao Zhou,1,* Qi-Zhi Yao,2 Jie ni,1 and Gu Jin2 1CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, P.R. China 2School of Chemistry and Materials, University of Science and Technology of China, Hefei 230026, P.R. China absTracT Highly oriented aragonite tablets

Introduction Carbon in the deep Earth consists of a primordial component plus carbonate that has recycled into the Earth’s mantle via subduction zones ( Dasgupta and Hirschmann 2010 ; Kelemen and Manning 2015 ). In the solid state, carbon has limited solubility in mantle silicates and therefore resides chiefly in carbon-rich accessory phases, either as oxidized carbonate or reduced graphite, diamond, or carbide ( Shcheka et al. 2006 ). Aragonite is one of the two most common forms of calcium carbonate found at the Earth’s surface and is formed by both biological

References Elfil H, Roques H (2001) Desalination 137: 177-186. Elfil H, Roques H (2004) AIChE Journal 50 (8): 1908-1916. Fellner P, Jurišová J, Pach L (2011) Acta Chimica Slovaca 4 (2):3-10. Patent application "Method of production of needle-like aragonite from waste calcium hydroxide". PP; ÚPV-SR 00142-2011; Authors: Ladislav Pach, Pavel Fellner, Jana Jurišová (FCHPT STU Bratislava), Juraj Gigac, Štefan Boháček (VÚPC, Bratislava).

American Mineralogist, Volume 98, pages 1074–1077, 2013 0003-004X/13/0506–1074$05.00/DOI: http://dx.doi.org/10.2138/am.2013.4410 1074 Letter High-pressure aragonite phenocrysts in carbonatite and carbonated syenite xenoliths within an alkali basalt VratisLaV Hurai,1,* Monika HuraioVá,2 rastisLaV MiLoVský,3 JarMiLa LuptákoVá,3 and Patrik konečný4 1Geological Institute, Slovak Academy of Sciences, Dúbravská cesta 9, 840 05 Bratislava, Slovakia 2Department of Mineralogy and Petrology, Comenius University, Mlynská dolina, 842 15 Bratislava, Slovakia 3

American Mineralogist, Volume 97, pages 707–712, 2012 0003-004X/12/0004–707$05.00/DOI: http://dx.doi.org/10.2138/am.2012.3923 707 Crystal structure and thermal expansion of aragonite-group carbonates by single-crystal X-ray diffraction Yu Ye,1,* Joseph R. smYth,2 and paul Boni2 1Department of Physics, University of Colorado, Boulder, Colorado 80309, U.S.A. 2Department of Geological Sciences, University of Colorado, Boulder, Colorado 80309, U.S.A. aBstRact Crystal structures of four aragonite-group carbonates—aragonite (Ca0.997Sr0.003CO3), calcian stronti

Zeitschrift für Kristallographie, Bd. 141, S. 11-24 (1975) Topotactic reaction of aragonite to hydroxyapatite* By W. Eysel** and DellaM. Roy Materials Research Laboratory, The Pennsylvania State University Pennsylvania*** (Received 31 May 1974) Auszug Die rhombische Aragonit-Struktur kann durch eine pseudohexagonale Zelle mit a — 9,38, c = 5,74 A und y = 117° beschrieben werden, deren Basis der- jenigen von Apatit (a = 9,43, c = 6,88 A, y = 120°) sehr ähnlich ist. Darüber hinaus existiert eine „grobe" zweidimensionale Strukturbeziehung, die schema- tisch durch

CHEMISTRY AND MINERALOGY OF EARTH’S MANTLE P-V-T equation of state and high-pressure behavior of CaCO3 aragonite† Ying Li1,2,*, Yongtao Zou1, ting Chen3, Xuebing Wang3, Xintong Qi3, haiYan Chen1, Jianguo Du2 anD baosheng Li1 1Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100, U.S.A. 2CEA Key Laboratory of Earthquake Prediction (Institute of Earthquake Science), China Earthquake Administration, Beijing, 100036, China 3Department of Geosciences, Stony Brook University, Stony Brook, New York 11794-2100, U.S.A. abstraCt The equation

American Mineralogist, Volume 93, pages 1608–1612, 2008 0003-004X/08/0010–1608$05.00/DOI: 10.2138/am.2008.2820 1608 A lattice dynamical study of the aragonite and post-aragonite phases of calcium carbonate rock W. Sekkal,1 N. Taleb,2 a. Zaoui,2,* aNd i. Shahrour2 1Condensed Matter Group, International Center for Theoretical Physics, Strada Costiera 11, 34014 Trieste, Italy 2L.M.L. (UMR 8107), Polytech’Lille, Université des Sciences et Technologies de Lille, Cité scientifique, Avenue Paul Langevin, 59655 Villeneuve D’Ascq Cedex, France abSTracT A recent

during subduction to the mantle, experimental constraints on thermodynamic behavior of CaCO 3 are needed at lower-mantle conditions. At mantle pressure and temperature ( P - T ) conditions, multiple polymorphic phase transitions of CaCO 3 have recently been discovered and debated, with potentially important effects on melting and other chemical reactions in the mantle. Calcite is stable up to ~3 GPa and then transforms to aragonite with space group Pnma (CaCO 3 - Pnma ), which remains stable through the transition zone and shallow lower mantle (e.g., Litasov et al

(1939) to recent static and dynamic high-pressure studies (e.g., Tyburczy and Ahrens 1986; Biellmann et al. 1993; Fiquet et al. 1994; Martinez et al. 1995, 1996; Suito et al. 2001; Luth 2001; Ivanov and Deutsch 2002). It is generally known that calcite transforms to aragonite, which often occurs in high-pressure metamorphic rocks, at high P-T that correspond to the lower crust and the uppermost upper mantle. It is unknown whether aragonite transforms to a new high-pressure phase in the deep mantle. In this study, therefore, the high-pressure stability limit