This image samples the excellent bedrock exposures north of Terby Crater, which lies on the northern rim of the giant Hellas basin.
An enhanced-color cutout shows a sample of this bedrock, which has a variety of colors and textures. The warm-colored bedrock probably contains hydrated minerals such as clays, whereas the blue-green bedrock is dominated by unaltered mafic minerals. These may be some of the oldest rocks exposed at the Martian surface. Such ancient rocks are extremely rare on Earth. [More at link]