A rind that appears bluish in this false-color view covers portions of the surface of a rock called "Whitewater Lake" in the top half of the view from NASA's Mars Exploration Rover Opportunity. This rind is similar in appearance to weathering rinds previously seen by Opportunity on rocks elsewhere within the Meridiani Planum region where the rover has worked since landing in 2004. Whitewater Lake is in the "Matijevic Hill" portion of the "Cape York" segment of the rim of Endeavour Crater.
The three exposures through different filters that were composited into this image were taken by Opportunity's panoramic camera (Pancam) during the mission's 3,064th Martian day, or sol (Sept. 6, 2012). The view is presented in false color that enhances color differences among various geological materials in the scene.
Whitewater Lake is the large flat rock in the top half of the image. From left to right it is about 30 inches (0.8 meter) across. The dark blue nubby rock to the lower left is "Kirkwood," which bears non-hematite spherules shown in a close-up image at https://photojournal.jpl.nasa.gov/catalog/PIA16139 . The rocks to the lower right look like breccias -- a type of rock containing jumbled fragments cemented together. They resemble other rocks in the area classed as the Shoemaker formation, which is hypothesized to hold deposits of material ejected when an impact excavated Endeavour Crater billions of years ago.