RGB color-composites images of six different bright features produced using coregistered monochrome images acquired at 882.1 nm, 649.2 nm, and 360.0 nm as the R, G, and B color channels, respectively. Regions of interest (ROIs) of about 10 to 20 pixels defined over the bright features (red) and nearby over the surrounding dark terrain (green) are represented in the insets. They are used to calculate the average reflectance spectra and compute the spectral ratios shown in Fig. 9. a) Anuket. Subset of OSIRIS NAC image: NAC_2014-09-05T02.35.55.531Z_ID30_1397549700; b) Khepry-Imhotep. Subset of OSIRIS NAC image: NAC_2014-09-16T15.09.00.365Z_ID30_ 1397549700; c) Khepry. Subset of OSIRIS NAC image: NAC_2014-09-16T16.24.25.334Z_ID30_1397549500; d) Imhotep. Subset of OSIRIS NAC image: NAC_2014-09-05T06.35.55.557Z_ID30_1397549300; e) Imhotep. Subset of OSIRIS NAC image: NAC_2014-09-16T21.48.48.383Z_ID30_1397549100.