This close-up image taken by the Mars Exploration Rover Spirit highlights the nobular nuggets that cover the rock dubbed "Pot of Gold." These nuggets appear to stand on the end of stalk-like features. The surface of the rock is dotted with fine-scale pits. Data from the rover's scientific instruments have shown that Pot of Gold contains the mineral hematite, which can be formed with or without water.
Scientists are planning further observations of this rock, which they hope will yield more insight into the hematite's origins as well as how the enigmatic nuggets formed.
This image was taken by Spirit's microscopic imager on sol 163 (June 18, 2004). The observed area is 3 centimeters by 3 centimeters (1.2 inches by 1.2 inches).