This enhanced color HiRISE image shows several craters somewhere in the southern mid-latitudes of Mars. It is currently mid-winter in the Southern hemisphere, so we can observe accumulating frost (neon blues) on pole-facing slopes (i.e. south-facing) and in shadowed areas.
However, the bluish deposits and ejecta deposits associated with the smaller crater we see are not consistent with frost deposits. These materials are most likely iron-bearing minerals that have not been previously oxidized (i.e., rusted), and have only recently been exposed to the surface when this small well-preserved crater was… [More at link]