Images
Olivine on Earth
October 30, 2012
The Martian soil examined by the Chemistry and Mineralogy (CheMin) instrument on NASA's Curiosity rover shows the diffraction signature, or "fingerprint," of the mineral olivine, shown here on Earth in the form of tumbled crystals about a quarter-inch (several millimeters) in size. The semi-precious gem peridot is a variety of olivine.