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Submicroscopical twinning in lunar and experimentally deformed pyroxenes

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During deformation experiments at high pressures (10 kb) and medium temperatures (500–650°) diopside became twinned on {100} in small optically invisible domains. If host and twin occur with equal frequency, the X-ray single-crystal photograph would show orthorhombic symmetry due to the special geometry of the diopside lattice. A crystal of pyroxene from Mare Tranquillitatis has been found to give just such an X-ray photograph with orthorhombic symmetry; this is explained as a possible deformation product.

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Wenk, H.-. Submicroscopical twinning in lunar and experimentally deformed pyroxenes. Contr. Mineral. and Petrol. 26, 315–323 (1970). https://doi.org/10.1007/BF00390080

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  • High Pressure
  • Mineral Resource
  • Diopside
  • Equal Frequency
  • Medium Temperature