High-temperature phase relations and topological constraints in the quaternary system MgO-Al2O3-SiO2-Cr2O3: An experimental study
-
Cristiano Brigida
and
Massimiliano Valle
Abstract
Phase relationships in the system MgO-Al2O3-SiO2-Cr2O3 (MASCr) were investigated experimentally from 1250 to 1560 °C using a 1-atm vertical quench furnace on 12 oxide mixtures covering a wide range of chemical compositions. Spinel, corundum, mullite, and sapphirine were found to display a wide range of solid solutions toward CR-rich end-members, whereas enstatite, cordierite, forsterite, and glasses were always Cr-poor. Glasses formed in relatively MgO-rich bulk compositions from 1250 °C, in assemblage with cordierite, enstatite, forsterite, and spinel, suggesting a lowering of the eutectic minimum in MASCr compared to available melting relationships in the model system MAS. Although unexpected, the relatively low-temperature melting of Cr-bearing mixtures is supported by topological constraints in the subsystems SACr and MSCr. The extent of Cr solubility in mullite has been found to reach ~14 wt% at 1560 °C, and 33 wt% in sapphirine at 1340 °C, which are the highest Cr values reported so far for these minerals. Liquidus surfaces are constrained by glass compositions that are displaced systematically toward silica compared to corresponding liquids in the ternary system MAS. As a consequence, the primary crystallization fields of Cr-spinel, Cr-sapphirine, and Cr-mullite are found to face the cristobalite/tridymite primary fields. A tentative liquidus diagram for the system MgO-Al2O3-SiO2-Cr2O3 is proposed, which could serve as a basis for the interpretation of the high-temperature evolution of planetary materials as well as for the development of new ceramic materials.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Single-crystal FTIR and X-ray study of vishnevite, ideally [Na6(SO4)][Na2(H2O)2](Si6Al6O24)
- Crystallographic texture and microstructure of terebratulide brachiopod shell calcite: An optimized materials design with hierarchical architecture
- High-temperature phase relations and topological constraints in the quaternary system MgO-Al2O3-SiO2-Cr2O3: An experimental study
- Tilt and buckling modes, and acoustic anisotropy in layers with post-perovskite connectivity
- Optical absorption study of natural garnets of almandine-skiagite composition showing intervalence Fe2+ + Fe3+ → Fe3+ + Fe2+ charge-transfer transition
- Deriving formation constants for aqueous metal complexes from XANES spectra: Zn2+ and Fe2+ chloride complexes in hypersaline solutions
- Birnessite polytype systematics and identiÞ cation by powder X-ray diffraction
- Improved measurement of fission-track annealing in apatite using c-axis projection
- Improved modeling of fission-track annealing in apatite
- Intercalibration of FTIR and SIMS for hydrogen measurements in glasses and nominally anhydrous minerals
- Order and miscibility in the otavite–magnesite solid solution
- An infrared investigation of the otavite-magnesite solid solution
- Partitioning of calcium, magnesium, and transition metals between olivine and melt governed by the structure of the silicate melt at ambient pressure
- The geometric effects of VFe2+ for VMg substitution on the crystal structures of the grandidierite-ominelite series
- The iron oxidation state of garnet by electron microprobe: Its determination with the flank method combined with major-element analysis
- Gram-Charlier development of the atomic displacement factors into mineral structures: The case of samsonite, Ag4MnSb2S6
- Superstructure of Challis mordenite with doubled monoclinic unit cell
- Biopyribole evolution during tremolite synthesis from dolomite and quartz in CO2-H2O fluid
- The evolution of diamond morphology in the process of dissolution: Experimental data
- The pearceite-polybasite group of minerals: Crystal chemistry and new nomenclature rules
- Determination of layer stacking microstructures and intralayer transition of illite polytypes by high-resolution transmission electron microscopy (HRTEM)
- Structural behavior of Al3+ in peralkaline, metaluminous, and peraluminous silicate melts and glasses at ambient pressure
- The crystal structure of ingersonite, Ca3Mn2+Sb45+O14, and its relationships with pyrochlore
- Chemical composition, statistical analysis of the unit cell, and electrostatic modeling of the structure of Al-saturated chlorite from metamorphosed rocks
- XANES study of the oxidation state of Cr in lower mantle phases: Periclase and magnesium silicate perovskite
- Crystal chemistry of hydration in aluminous orthopyroxene
Articles in the same Issue
- Single-crystal FTIR and X-ray study of vishnevite, ideally [Na6(SO4)][Na2(H2O)2](Si6Al6O24)
- Crystallographic texture and microstructure of terebratulide brachiopod shell calcite: An optimized materials design with hierarchical architecture
- High-temperature phase relations and topological constraints in the quaternary system MgO-Al2O3-SiO2-Cr2O3: An experimental study
- Tilt and buckling modes, and acoustic anisotropy in layers with post-perovskite connectivity
- Optical absorption study of natural garnets of almandine-skiagite composition showing intervalence Fe2+ + Fe3+ → Fe3+ + Fe2+ charge-transfer transition
- Deriving formation constants for aqueous metal complexes from XANES spectra: Zn2+ and Fe2+ chloride complexes in hypersaline solutions
- Birnessite polytype systematics and identiÞ cation by powder X-ray diffraction
- Improved measurement of fission-track annealing in apatite using c-axis projection
- Improved modeling of fission-track annealing in apatite
- Intercalibration of FTIR and SIMS for hydrogen measurements in glasses and nominally anhydrous minerals
- Order and miscibility in the otavite–magnesite solid solution
- An infrared investigation of the otavite-magnesite solid solution
- Partitioning of calcium, magnesium, and transition metals between olivine and melt governed by the structure of the silicate melt at ambient pressure
- The geometric effects of VFe2+ for VMg substitution on the crystal structures of the grandidierite-ominelite series
- The iron oxidation state of garnet by electron microprobe: Its determination with the flank method combined with major-element analysis
- Gram-Charlier development of the atomic displacement factors into mineral structures: The case of samsonite, Ag4MnSb2S6
- Superstructure of Challis mordenite with doubled monoclinic unit cell
- Biopyribole evolution during tremolite synthesis from dolomite and quartz in CO2-H2O fluid
- The evolution of diamond morphology in the process of dissolution: Experimental data
- The pearceite-polybasite group of minerals: Crystal chemistry and new nomenclature rules
- Determination of layer stacking microstructures and intralayer transition of illite polytypes by high-resolution transmission electron microscopy (HRTEM)
- Structural behavior of Al3+ in peralkaline, metaluminous, and peraluminous silicate melts and glasses at ambient pressure
- The crystal structure of ingersonite, Ca3Mn2+Sb45+O14, and its relationships with pyrochlore
- Chemical composition, statistical analysis of the unit cell, and electrostatic modeling of the structure of Al-saturated chlorite from metamorphosed rocks
- XANES study of the oxidation state of Cr in lower mantle phases: Periclase and magnesium silicate perovskite
- Crystal chemistry of hydration in aluminous orthopyroxene
