Structural, Micro-Structural and Thermal Characterizations of Natural Garnet of Regions of Patharkhola from the State of Uttarakhand of India
DOI:
https://doi.org/10.48165/bpas.2023.42F.1.1Keywords:
Natural Garnet, Crystal Structure, Pressure-Temperature Phase transition, Microstructure, Thermal Behaviour, Lesser Kumaun HimalayaAbstract
Garnet is an important group of nesosilicate minerals. These minerals are widespread in the earth’s crust and the upper mantle as a major rock forming minerals. In petrology, they are frequently used as a geothermobarometers to understand the Pressure-Temperature (P-T) history of rock assemblage, which involve many equilibrium reactions occurring in the Earth’s upper mantle. The garnets have been widely studied especially on electrical, magnetic and thermodynamic properties, as far as the properties are concerned. Natural Garnet grains obtained from Garnet-mica schist of Patharkhola area have been investigated using various techniques, such as SEM, XRD, DSC-TGA to study their structural and thermal properties. The crystal morphology obtained by SEM has been found in accordance with the XRD data crystallizing in cubic system refined in Ia3d space group making it pyrope to almandine rich garnet. DSC curve shows gentle endothermic peak of heat flow showing its decomposition at higher temperature while the gentle slope of TGA curve shows it to be more magnesium rich respectively.
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