Scanning electron microscopy (SEM) methods are widely used in the geosciences to determine grain shape and surface characteristics using SEM–secondary electron and backscatter imagery (SEM-SE/BSE) and elemental composition of minerals using SEM–energy dispersive X-ray spectroscopy (SEM-EDS). We discuss applications and best practices for utilizing widely available SEM methods for luminescence dating, including (1) checking sample purity following mineral separation, (2) imaging grain shape and surface characteristics related to weathering and transport, (3) quantifying feldspar-mineral phases in feldspar separates, and (4) determining internal potassium concentration (wt% K) in feldspars for use in estimating internal beta contribution to the dose rate for a sample.

Quartz and feldspar purification checks of mineral separates require the least sample preparation and instrument time. These methods utilize the “environmental” or “low-vacuum” conditions of SEM. These conditions are less conducive to acquiring high-quality compositional data but can be used to quickly determine sample purity.

Conversely, to acquire higher-quality compositional data, SEM working conditions require high vacuum and accelerating voltages. The resulting semiquantitative SEM-EDS results can be used to determine the phase composition of feldspar separates and more accurately determine the internal potassium content for dose-rate and age calculations.