Investigations on the impact of broad ion beam milling preparation on coal samples

This data release presents the results of broad ion beam (BIB) milling tests on organic-rich geologic samples by comparing the changes in vitrinite reflectance (Ro) pre- and post-milling. This work utilized two different BIB milling systems (single gun and dual gun) and evaluated changes in Ro using different ion milling voltages (2–8 keV), and sample temperature (cooling vs. standard, non-cooling stages) on seven coals with thermal maturities ranging from 0.6–1.74% Ro. These experiments are important for helping determine if BIB milling is a viable method for preparing organic-rich samples for Ro analysis beyond what is typically achieved through traditional polishing methods.