Close-up and deconvolution of the individual bands for the global spectra (corresponding to the maps of Figs. 3 and 4) recorded for sample A0108-15 (03-top-a), upper spectrum, with a high physisorbed and/or interlayer water contribution, and C0040-FC025 (bot-b), second spectrum from top, dominated by the OH hydroxyl contribution. Individual bands are represented by hatching: OH stretch (blue in the 3000–3700 cm⁻¹ region), CH stretch (magenta), C=0 carbonyl stretch (brown), OH bending (blue around 1640 cm⁻¹), aromatic C=C bending (black), carbonates (red), and silicates (green). Each wavenumber range is normalised with regard to the high wavenumber range by a factor (indicated in parenthesis) for clarity of the deconvolution. The spectrum of a particularly C-aromatic-rich grain, C0109-04 (top-a), is also shown. For comparison, a spectrum taken from Orgueil, which was prepared and recorded in the same conditions as the Ryugu samples, is shown at the bottom. See text for details.