Rare earth element ore grade estimation of mineralized drill core from hyperspectral imaging spectroscopy

摘要

The mineralogy of rare earth element deposits is critical in understanding their petrogenesis and has significant implications for their economic viability, which is determined by more than ore grade alone. Rapid determination of relative ore modal mineralogy for these deposit types by hyperspectral reflectance spectroscopy would provide immediate feedback on the tenor, type and relevance of mineralization. This research builds upon mineralogical characterization and reflectance spectroscopy studies in the visible to short wave infrared region (VNIR and SWIR) of important rare earth element ore minerals (e.g., bastnaesite, monazite, xenotime, eudialyte) and provides preliminary interpretations of REE-mineralized drill core using hyperspectral imagery. The diagnostic absorptions caused by f-orbital electrons also allows for simple ore grade approximation of selected lanthanides. Training and subsequent validation of hyperspectral-based results is achieved through conventional geochemical assays, and modal mineralogy determined by Rietveld refinement of powder x-ray diffraction experiments.