Geochemistry of braunite and associated phases in metamorphosed non-calcareous manganese ores of India
@article{Bhattacharyya1984GeochemistryOB, title={Geochemistry of braunite and associated phases in metamorphosed non-calcareous manganese ores of India}, author={P. K. Bhattacharyya and Somnath Dasgupta and Masato Fukuoka and Supriya Roy}, journal={Contributions to Mineralogy and Petrology}, year={1984}, volume={87}, pages={65-71} }
In the metamorphosed manganese oxide ores of India, braunite is ubiquitous in all assemblages from chlorite to sillimanite grades. Chemical analyses of braunite from different prograde assemblages confirm the presence of a fixed R2+ (=Mn2++Mg+Ca) SiO3 molecule in the mineral. Element partitioning between coexisting braunite and bixbyite indicates a near-ideal mixing of Fe+3/ -Mn+3 in the phases. This also indicates that braunite became relatively ferrian while equilibrating with associated…
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