Hyperspectral and Petro – Chemical Signatures study on Corundum Bearing Amphibolite Schist of Magadi Area, Ramanagara District, Karnataka, India

Corundum is best known for its gem varieties, Ruby and Sapphire. Corundum is a very hard, tough, and stable mineral. For all practical purposes, it is the hardest mineral after Diamond, making it the second hardest mineral. Precambrian basement rocks of Karnataka composed of active and dynamic geological settings with economic mineral deposits and variety of gemstones. These gemstones were noticed all along the lithological contacts of Green stone & Schist Belts, adjesent to younger granites and granitoids of Dharwar Craton of southern Karnataka. Magadi area comes to Ramanagara district, it has three kinds of litho units with economically viable minerals including gemstones varieties particularly in contact zones of ultramafics, amphibolite schist with gneiss and younger granites. Random samples were collected such as gneiss, and corundum bearing Amphibolite schist through GTC (Ground Truth Check). The study carried out by geological, petrochemical and Hyperspectral signature using advent high-tech tools of Spectro- Radiometer (Spectral Evolution SR-3500) instrument, DARWin SP.V.1.3.0 and GIS software's. The spectral signatures of the collected samples were derived in laboratory environment to achieve better accuracy. Hyperspectral (350-2500nm) were developed as works mainly on physico-chemical and optical properties of the litho units which help in mapping of precious gemstones at lithological contacts and mineralized zones. The present study aims to charactrize the spectral behavior of Corundum and associated rocks of the study area. Spectral radiometer instrument bring out diagnostic features on lithological contact for better discrimination of verity gemstones and altered minerals. The final results highlight the spectral characters of corundum and associated rocks for better mapping of Magadi area of Ramnagara district in Precambrian Amphibolite schist rocks and similar terrains of Karnataka State.