Returning to the Rover, they drove 650 ft (200 m) to a large boulder (Station 6A). Even walking short distances on the slope was time consuming so it was easier to just have the crew use the Rover to get there. The boulder was 10 ft (3 m) across. It was necessary for one crewmember to stay by the Rover, holding it to make sure it did not slide down the hill, which now had a 15-degree slope. With time running out on the stop, Scott was able to confirm what Irwin had seen earlier — the rock had a greenish tinge. The color was found to come from magnesium oxide.
