Characterization of a high-pressure phase of silica from the Martian meteorite Shergotty

  title={Characterization of a high-pressure phase of silica from the Martian meteorite Shergotty},
  author={Przemyslaw K. Dera and Charles T. Prewitt and Nabil Z. Boctor and Russell J. Hemley},
  journal={American Mineralogist},
  pages={1018 - 1023}
Abstract Recently, there has been substantial interest in post-stishovite high-pressure polymorphs of SiO2, discovered as extraterrestrial minerals, or synthesized in the laboratory. Previous investigators reported the presence of “α-PbO2-like” and “baddeleyite-like” SiO2 in the Martian meteorite Shergotty, and also the synthesis of an a-PbO2-like phase at pressures of 60-80 GPa in a laser-heated diamond anvil cell. To provide definitive information about the nature of the natural “a-PbO2 phase… 

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