To better understand the mechanism of oxidation, we performed x-ray photoelectron spectroscopy (XPS). High-resolution scans of scandium and carbon were taken at 0 days, 1 day, and 11 days sitting in air (Figure ). Scandium shows four species at the initial timepoint, indicating several scandium species were present. Component A corresponds to (Sc 3+ ) , likely due to surface oxidation during transfer into the XPS. We observe one species (component B) at binding energy that were previously assigned to (Sc 2+ ) . We assume that component C is an intermediate species as the carbide transitions to the fully formed oxide, with peaks that lie between the component A and B doublets. Finally, there is a small peak with a low binding energy (395.6 eV), where it is unclear whether this is scandium or possibly nitrogen as the binding energy of peak is low for either element. There are four species at the initial timepoint for carbon, where component E and G are adventitious carbon and its oxidized counterpart, respectively . Component F is likely the carbide species, as peaks at a similar shift have been seen in other transition metal carbide species . The carbide peak energy in this material is relatively reduced compared to other known transition metal carbide species, which is not surprising from an electride. Component H is likely an intermediate species as the carbide oxidizes. After one day of exposure to air, the Sc 2+ peak decreases, the Sc 3+ peak increases, and the carbide carbon peak decreases in intensity, indicating the sample is oxidizing. In the carbon spectra, a new species, component I, becomes apparent, and likely results from the adventitious carbon oxidizing. At the 11-day timepoint, the peaks associated with Sc2C in both the scandium and carbon spectra have disappeared, indicating the surface was completely oxidized. The XRD data shows that there are still crystalline peaks present at the 11-day timepoint. From XRD and XPS, we conclude that an amorphous oxide forms on the surface of crystals first, and as the material continues to be exposed to air, oxygen diffuses further into the crystals until the bulk material becomes an amorphous oxide after 28 days. Therefore, handling this material in air will require passivating coatings.