  We analyze images of a rock on Ryugu acquired in situ by MASCam, camera of
the MASCOT lander, with the aim of identifying possible carbonaceous chondrite
(CC) analogs. The rock's reflectance ($r_{\rm F} = 0.034 \pm 0.003$ at phase
angle $4.5^\circ \pm 0.1^\circ$) is consistent with Ryugu's average
reflectance, suggesting that the rock is typical for this asteroid. A
spectrophotometric analysis of the rock's inclusions provides clues to CC group
membership. Inclusions are generally brighter than the matrix. The dominant
variation in their color is a change of the visible spectral slope, with many
inclusions being either red or blue. Spectral variation in the red channel
hints at the presence of the 0.7~$\mu$m absorption band linked to hydrated
phyllosilicates. The inclusions are unusually large for a CC; we find that
their size distribution may best match that of the Renazzo (CR2) and Leoville
(CV3) meteorites. The Ryugu rock does not easily fit into any of the CC groups,
consistent with the idea that typical Ryugu-type meteorites are too fragile to
survive atmospheric entry.
