NASA Scientists Discover Unexpected Mineral on Mars: Tridymite, which crystallizes at low pressures and high temperatures from high-SiO2 materials, was detected at high concentrations in a sedimentary mudstone in Gale crater, a finding that may alter our understanding of how the planet evolved.

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NASA Scientists Discover Unexpected Mineral on Mars: Tridymite, which crystallizes at low pressures and high temperatures from high-SiO2 materials, was detected at high concentrations in a sedimentary mudstone in Gale crater, a finding that may alter our understanding of how the planet evolved.