Though Neutron Activation Analysis (NAA), X-ray fluorescence (XRF), Proton
Induced X-ray Emission (PIXE) Spectroscopy, Raman spectroscopy etc.,
can be used for the determination of rare earths in a non-destructive way, NAA is not easily accessible to all the laboratories and XRF/PIXE
detection limits are comparatively poor [1,6–12].