Perpustakaan Digital ITB

The mapping of potential rare earth elements (REE) areas is important to meet increasing demand, thus, making innovation in mineral exploration necessary. As a fast, non-destructive mapping method, reflectance spectroscopy shows strong promise. It is known that the reflectance spectra signature for REE-bearing minerals can be identified in the visible near-infrared (400–1100 nm) range. This research aimed to implement reflectance spectroscopy for the identification of REE-bearing minerals in samples from several alluvial tin mines in South Bangka, Indonesia. Reflectance spectroscopy was carried out for samples consisting of alluvial tin deposits, tailing, and concentrates. Furthermore, the samples were divided into 3 differently sized fractions: +48, +100, and -100 mesh. The spectral reflectance data were acquired using the spectroradiometer, and REE concentrations were measured using inductively coupled plasma mass spectrometer analysis. REE-bearing minerals, such as monazite and xenotime, were more commonly found in the tailing and concentrate samples, while a small amount was identified in the alluvial samples. The spectral analysis showed that wavelengths of 748 nm, 803 nm, and 872 nm can be related to REE, and they are also found to be suitable with remote sensing imagery of Sentinel-2, which indicates a capability of the image to detect REE-bearing minerals.