This mosaic of five images taken by the microscopic imager on the Mars Exploration Rover Opportunity on sol 87 shows the hole drilled by the rover's rock abrasion tool into the rock dubbed "Pilbara." A sliced "blueberry," or spherule, which is darker and harder than the rest of the rock, can be seen near the center of the hole. The rock abrasion process left a pile of rock powder around the side of the hole, and to a lesser degree, inside the hole. The hole is 7.2 millimeters (about 0.28 inches) deep and 4.5 centimeters (about 1.8 inches) in diameter.
Because the original images of this hole had areas of bright sunlight as well as shadow, the images making up this mosaic have been arranged to hide as much of the sunlit area as possible. The white spot is one area that could not be covered by other images. It is possible to stretch the image so that features in this white spot are visible, but this makes the rest of the mosaic harder to view. The bright streaks on the bottom part of the hole are most likely reflections from various parts of the robotic arm. The geometric and brightness seams have been corrected in this image.