Petrography and Laser Raman Characterization of Banded Hematite Jasper from Agori Formation of Mahakoshal Greenstone Belt

The Laser Raman Micro Spectroscopy (LRMS) technique has been used to analyzed ore forming processes in the Banded Iron Jasper (BHJ). Petrographic studies of BHJ sample indicates that variable amounts of cryptocrystalline silica rich matrix occur asjasper or chert associated with hematite crystals. Jasper and hematite phases display characteristics Raman Shift approximately 466 cm-1 and 1318 cm-1 attributed to vibrational stretching mode (SiO-Si) and two-phonon longitudinal optical (2LO) vibrational modes (Fe-O). Here, we investigated the effects of the Raman mapping of hematite crystal in the silica rich matrix as jasper. Our results clearly demonstrate that crystallization of hematite crystals with jasper in the Agori Formation precursors sequentially required supersaturated Fe-rich and Si-rich solution, uniform temperature and pressure conditions in the Paleoproterozoic Ocean and atmosphere.