Synthesis and characterization of K2Ca5(SO4)6·H2O, the equivalent of görgeyite, a rare evaporite mineral
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J. Theo Kloprogge
,
Liesel Hickey
Abstract
Görgeyite, K2Ca5(SO4)6·H2O, is a very rare monoclinic double salt found in evaporites related to the slightly more common mineral syngenite. At 1 atmosphere with increasing external temperature from 25 to 150 °C, the following succession of minerals was formed: first gypsum and K2O, followed at 100 °C by görgeyite. Changes in concentration at 150 °C due to evaporation resulted in the formation of syngenite and finally arcanite. Under hydrothermal conditions, the succession is syngenite at 50 °C, followed by görgyeite at 100 and 150 °C. Increasing the synthesis time at 100 °C and 1 atmosphere showed that initially gypsum was formed, later being replaced by görgeyite. Finally görgeyite was replaced by syngenite, indicating that görgeyite is a metastable phase under these conditions. Under hydrothermal conditions, syngenite plus a small amount of gypsum was formed, after two days being replaced by görgeyite. No further changes were observed with increasing time. Pure görgeyite showed elongated crystals approximately 500 to 1000 μm in length. The infrared and Raman spectra are mainly showing the vibrational modes of the sulfate groups and the crystal water (structural water). Water is characterized by OH-stretching modes at 3526 and 3577 cm-1, OH-bending modes at 1615 and 1647 cm-1, and an OH-libration mode at 876 cm-1. The sulfate ν1 mode is weak in the infrared but showed strong bands at 1005 and 1013 cm-1 in the Raman spectrum. The ν2 mode also showed strong bands in the Raman spectrum at 433, 440, 457, and 480 cm-1. The ν3 mode is characterized by a complex set of bands in both infrared and Raman spectra around 1150 cm-1, whereas ν4 is found at 650 cm-1.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Composition and I4/m-P42/n phase transition in scapolite solid solutions
- Synthesis and characterization of K2Ca5(SO4)6·H2O, the equivalent of görgeyite, a rare evaporite mineral
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- The speciation of dissolved H2O in dacitic melt
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- Experimental determination of siderite stability and application to Martian Meteorite ALH84001
- Determination of the molar absorption coefficient for the infrared absorption band of CO2in rhyolitic glasses
- Crystallographic properties of the calcium phosphate mineral, brushite, by means of First Principles calculations
- The crystal structure of jonesite, Ba2(K,Na)[Ti2(Si5Al)O18(H2O)](H2O)n: A first example of titanosilicate with porous double layers
- Crystal-chemistry of talc: A near infrared (NIR) spectroscopy study
- Synthesis of beryllian sapphirine in the system MgO-BeO-Al2O3-SiO2-H2O and comparison with naturally occurring beryllian sapphirine and khmaralite, Part 2: A chemographic study of Be content as a function of P, T, assemblage and FeMg–1exchange
- Spriggite, Pb3[(UO2)6O8(OH)2](H2O)3, a new mineral with β-U3O8–type sheets: Description and crystal structure
- Sieve-textured plagioclase in dacitic magma: Interference imaging results
- Single crystal raman spectroscopy of cerussite
- Sodalite: High-temperature structures obtained from synchrotron radiation and Rietveld refinements
- The structure of metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, by in situ synchrotron powder diffraction
- High-pressure synchrotron X-ray diffraction study of spessartine and uvarovite: A comparison between different equation of state models
- Quantum calculations of the electronic structure and NMR quadrupolar interaction parameters for tugtupite
- Identification of pyrite valence band contributions using synchrotron-excited X-ray photoelectron spectroscopy
- Micro-Raman studies of gypsum in the temperature range between 9 K and 373 K
- A new rare earth disilicate (REE2Si2O7; REE = Dy, Tm, Lu; type-L): Evidence for nonquenchable 10 GPa polymorph with silicon in fivefold trigonal bipyramidal coordination?
- Structural variations in the brownmillerite series Ca2(Fe2–xAlx)O5: Single-crystal X-ray diffraction at 25 °C and high-temperature X-ray powder diffraction (25 °C ≤ T ≤ 1000 °C)
- Peculiarity and defect structure of the natural and synthetic zeolite mordenite: A single-crystal X-ray study
- Model independent phase equilibrium constraints on the ferrosilite activity in the binary Fe-Mg orthopyroxene solid solution
- Microstructural study of synthetic sintered diamond and comparison with carbonado, a natural polycrystalline diamond
- Structural and chemical response to varying [4]B content in zoned Fe-bearing olenite from Koralpe, Austria
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Articles in the same Issue
- Composition and I4/m-P42/n phase transition in scapolite solid solutions
- Synthesis and characterization of K2Ca5(SO4)6·H2O, the equivalent of görgeyite, a rare evaporite mineral
- Phase relations in the system Fe-FeSi at 21 GPa
- The speciation of dissolved H2O in dacitic melt
- Nucleation and growth kinetics of the α-β transformation in Mg2SiO4determined by in situ synchrotron powder X-ray diffraction
- Experimental determination of siderite stability and application to Martian Meteorite ALH84001
- Determination of the molar absorption coefficient for the infrared absorption band of CO2in rhyolitic glasses
- Crystallographic properties of the calcium phosphate mineral, brushite, by means of First Principles calculations
- The crystal structure of jonesite, Ba2(K,Na)[Ti2(Si5Al)O18(H2O)](H2O)n: A first example of titanosilicate with porous double layers
- Crystal-chemistry of talc: A near infrared (NIR) spectroscopy study
- Synthesis of beryllian sapphirine in the system MgO-BeO-Al2O3-SiO2-H2O and comparison with naturally occurring beryllian sapphirine and khmaralite, Part 2: A chemographic study of Be content as a function of P, T, assemblage and FeMg–1exchange
- Spriggite, Pb3[(UO2)6O8(OH)2](H2O)3, a new mineral with β-U3O8–type sheets: Description and crystal structure
- Sieve-textured plagioclase in dacitic magma: Interference imaging results
- Single crystal raman spectroscopy of cerussite
- Sodalite: High-temperature structures obtained from synchrotron radiation and Rietveld refinements
- The structure of metahohmannite, Fe3+2[O(SO4)2]⋅4H2O, by in situ synchrotron powder diffraction
- High-pressure synchrotron X-ray diffraction study of spessartine and uvarovite: A comparison between different equation of state models
- Quantum calculations of the electronic structure and NMR quadrupolar interaction parameters for tugtupite
- Identification of pyrite valence band contributions using synchrotron-excited X-ray photoelectron spectroscopy
- Micro-Raman studies of gypsum in the temperature range between 9 K and 373 K
- A new rare earth disilicate (REE2Si2O7; REE = Dy, Tm, Lu; type-L): Evidence for nonquenchable 10 GPa polymorph with silicon in fivefold trigonal bipyramidal coordination?
- Structural variations in the brownmillerite series Ca2(Fe2–xAlx)O5: Single-crystal X-ray diffraction at 25 °C and high-temperature X-ray powder diffraction (25 °C ≤ T ≤ 1000 °C)
- Peculiarity and defect structure of the natural and synthetic zeolite mordenite: A single-crystal X-ray study
- Model independent phase equilibrium constraints on the ferrosilite activity in the binary Fe-Mg orthopyroxene solid solution
- Microstructural study of synthetic sintered diamond and comparison with carbonado, a natural polycrystalline diamond
- Structural and chemical response to varying [4]B content in zoned Fe-bearing olenite from Koralpe, Austria
- A new dense silica polymorph: A possible link between tetrahedrally and octahedrally coordinated silica
- Epitaxial relationships of clinopyroxene-hosted magnetite determined using electron backscatter diffraction (EBSD) technique
