Mysterious mineral on Mars was spat out by an explosive eruption 3 billion years ago - Livescience.com

NASA's Curiosity rover first uncovered the unusual mineral in 2015.

Silver-colored dust drilled from a rock by NASA's Curiosity rover on July 30, 2015. Analysis of the dust revealed it contained the mineral tridymite, which was very unexpected. (Image credit: NASA/JP… [+5984 chars]

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