<p>Studying the reflectance spectroscopy of minerals is an emerging technique in mineral exploration. This research primarily focuses on applying the Relative Absorption Band Depth (RBD) image processing method to ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite data to accurately map ferric iron oxide ore minerals in the Keonjhar district of Odisha, India. RBD is an effective three-point ratio technique for identifying diagnostic mineral absorption features. For each absorption feature, the numerator is calculated as the sum of the bands corresponding to the shoulders adjacent to the absorption feature, while the denominator is the band closest to the absorption minimum. It is important to note that RBD measures relative, not absolute, absorption. The resulting ASTER-based RBD image, computed as ((Band2 + Band4)/Band3), demonstrates improved mapping of ferric iron oxide ore in the study area compared to the previously used iron index (Band2/Band1) image. The ferric iron oxide ore mapping results derived from the RBD method are primarily validated by comparing them with the established geological map of the study area and by correlating the spectral signatures of image pixels associated with ferric iron oxide with laboratory-generated spectral signatures of hematite ore samples collected from the field. The methodology employed in this study can be applied to iron ore exploration in other regions with geological settings similar to those found in the Keonjhar district of Odisha, India.</p>