Left: spectral comparison of the 2.8 μm band between Klio and several samples, including the spectra of CCs published in Takir et al. (2013, 2019), the average spectrum of Ryugu’s bulk C published in Pilorget et al. (2021), and the average spectrum of the Bennu aggregate OREX-800029-0, published in Lauretta et al. (2024). The vertical dashed line indicate the position of Klio’s 2.8 μm feature (i.e. 2.776 μm). An offset have been applied to the spectra for better comparison. Right: dispersion graph between the relative band depth and the peak position of the 2.8 μm band in Klio, various CCs, Ryugu samples and Bennu samples (OREX-800029-0).