Natural Graphite from Neoproterozoic Psammitic Gneiss, Inanalo Mountain, Southern Madagascar

We report here, for the first time, powder X-ray diffraction, and laser-Raman spectroscopic data on the graphite samples from Inanalo mountain (S24°24 3 1 2" E45°23'18 3 ), 20 km east of the Ampanihy shear zone of the southern Madagascar Our experimental results show that the graphite is highly crystalline, and syngenetic with the degree of graphitisation varying from 148 to 180, ylelding the peak metarnorphic temperatures of 750 to 850°C Laser Raman spectroscopic studies show only ordered peak at around 1580 cm-' In the frequency range from I000 to 2000 cm-' The commonly observed disordered peak In natural graphite is found to be absent in the studied sample, indicating high-temperature metamorphism There is no flurd deposited graphite (epigenetlc graphlte) in the sample The peak metamorphic temperature obtained In the present study is found to be in good agreement withinat obtained from the conventional geothermometry studies on the sample from the Beraketa shear zone or the Betroka tectonic belt.