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The demand for iron ore has increased in the recent years, thereby necessitating the adoption of rapid and accurate
approaches to iron ore exploration and its grade-assessment. It is in this context that hyperspectral radiometry is seen as a
potential tool. This paper examines the potential of hyperspectral radiometry in the visible, NIR and SWIR regions of the
EMR to assess the grades of hematite of the western Singhbhum iron ore belt of eastern India, in a rapid manner. Certain
spectro-radiometric measurements and geochemical analysis were carried out and the results have been presented. From
the spectral measurements, it is seen that the strength of reflectance and absorption at definite wavelength regions is
controlled by the chemical composition of the iron ores. It is observed that the primary spectral characteristics of these
hematite lie in the 650-750nm, 850 to 900nm and 2130-2230nm regions. The laboratory based hyperspectral signatures
and multiple regression analysis of spectral parameters and geochemical parameters (Fe2O3% and Al2O3%) predicted the
concentration of iron and alumina content in the hematite. A very strong correlation (R2=0.96) between the spectral
parameters and Fe% in the hematite with a minimum error of 0.1%, maximum error of 7.4% and average error of 2.6% is
observed. Similarly, a very strong correlation (R2=0.94) between the spectral parameters and Al2O3% in the iron ores
with a minimum error of 0.04%, maximum error of 7.49% and average error of 2.5% is observed. This error is perhaps
due to the presence of other components (SiO2, TiO2, P2O etc.) in the samples which can alter the degree of reflectance
and hence the spectral parameters. Neural network based multi-layer perception (MLP) analysis of various spectral
parameters and geochemical parameters helped to understand the relative importance of the spectral parameters for
predictive models. The strong correlations (Iron: R2=0.96; Alumina: R2=0.94) indicate that the laboratory hyperspectral
signatures in the visible, NIR and SWIR regions can give a better estimate of the grades of hematite in a rapid manner.
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