Opportunity is investigating light-toned veins around the north end of Cape York on the rim of Endeavour Crater.

On Sol 2969 (May 31, 2012), the rover drove 36 feet (11 meters) to the northeast to approach one of these putative gypsum veins.

On Sol 2971 (June 2, 2012), Opportunity bumped about 8 feet (2.3 meters) to place the vein, now called "Monte Cristo," within the work volume of the robotic arm.

Taking advantage of the 3-sol weekend plan, the rover included an atmospheric argon measurement by the Alpha Particle X-ray Spectrometer (APXS) on Sol 2972 (June 3, 2012).

On Sol 2974 (June 5, 2012), Opportunity began the in-situ (contact) investigation of the vein Monte Cristo with a Microscopic Imager (MI) mosaic of an exposed portion of the vein, followed by the placement of the APXS for a multi-sol integration.

As of Sol 2974 (June 5, 2012), solar array energy production was 369 watt-hours with an atmospheric opacity (Tau) of 0.364 and a slightly improved solar array dust factor of 0.562.

Total odometry is 21.42 miles (34,469.86 meters).