Effect of Particle Size on Raman Signal Strength of Silicate Minerals

ABSTRACT Understanding the effects of particle size is necessary for quantifying minerals in mixtures using Raman spectroscopy. Raman signal intensity is evaluated using six common silicate minerals (two olivines, two pyroxenes, and two feldspars) at 10 particle size ranges. For olivines and feldspars, the highest peak intensities are observed in samples with 38–63 and 63–106 μm particle sizes. There is no such consistent trend for the pyroxene samples, although the overall low signal strength complicates those measurements. Raman spectra of samples with varying particle sizes appear to be influenced by two competing effects: scattering from particle boundaries and effective sampling volume.