Secondary hematite (SH) is a serious factor resulting in reduction degradation of iron ore sinter blast furnace; however, until now, quantitative study for SH formation had not been reported. In this work, the effects gangue composition, including MgO, Al2O3 and SiO2, on solid-state sintering process fines were investigated quantitatively. It shows that decreased from 67.84% to 46.11%, 35.44% 2...

Understanding crust–atmosphere interactions on Venus is fundamentally important to interpretations of Venus’ surface spectroscopic data. Olivine, in basaltic crust, oxidized under a heated CO2 atmosphere. However, the oxidation rates, product assemblages and spectral characteristics olivine samples with different Fa# values remain largely unclear. Herein, we investigated (Fa09, Fa29 Fa71) atmos...

Magnesioferrite spinel, MgFe2O4, was synthesized at 900 °C from equimolar amounts of reagentgrade oxides, MgO and Fe2O3, and quenched in air. The structural behavior of magnesioferrite was determined from in situ synchrotron X-ray powder-diffraction data [ = 0.92225(4) Å] at room pressure and temperatures from 28 to 982 °C on heating and cooling. The a unit-cell parameter increases linearly on ...

Introduction: Spinel minerals with 'normal' structure are common in extraterrestrial materials and can form via a large range of processes including nebular condensation, crystallization from liquid melts and sub-solidus metamor-phic reactions. Owing to their ability to accept a large range of cations in their crystal structures these minerals can be regarded as useful petrogenetic indicators w...

The eutectic mineral assemblage calcite-dolomitepericlase-apatite-forsterite-magnesioferrite-pyrrhotite-alabandite in a carbonatite dike within the Oka complex, Quebec, buffers the fugacities (and partial pressures) of all gas species in C-O-H-S-F, assuming vapor saturation. At the inferred eutectic (640 ~ C, 1 kbar), the most important gas species and their partial pressures (bars) were: H20, ...

Formation of natural diamonds requires the reduction of carbon to its bare elemental form, and pressures (P) greater than 5 GPa to cross the graphite-diamond transition boundary. In a study of shocked ferromagnesian carbonate at the Xiuyan impact crater, we found that the impact pressure-temperature (P-T) of 25-45 GPa and 800-900 °C were sufficient to decompose ankerite Ca(Fe2+,Mg)(CO3)2 to for...

Introduction: Oxygen fugacity (fO2) is an important factor in planetary formation and evolution. Certain minerals or assemblages of minerals are stable only under certain fO2 conditions (at a constant T and P) and can be recorders of ambient fO2 during geologic processes. The best estimate of oxygen fugacity from mineral assemblages has implications, from large-scale models of planetary evoluti...

During this study, we investigated the mineralogical characterization of technogenic magnetic particles (TMPs) contained in alkaline industrial dust and fly ash emitted by coal burning power plants and cement plants. The reaction of tested dust samples varied between values of pH 8 and pH 12. Their magnetic properties were characterized by measurement of magnetic susceptibility (χ), frequency d...