Abstract
Clinoenstatite crystals from a boninite and the Yamato-74191 chondrite have been studied with an analytical electron microscope. (100) twins and cracks perpendicular and parallel to the c axis are characteristic of their submicroscopic textures. The frequency in appearance along the c axis and widths of the cracks have been explained by the dimensional change of the c axis in the direct transformation of protoenstatite to clinoenstatite and by the cooling rate around the transformation temperature. The cracks in the crystals from the boninite are filled with fibrous crystals of talc, while those from the chondrite are open or filled with glass in which fine crystals of plagioclase are common.
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Yasuda, M., Kitamura, M. & Morimoto, N. Electron microscopy of clinoenstatite from a boninite and a chondrite. Phys Chem Minerals 9, 192–196 (1983). https://doi.org/10.1007/BF00311954
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DOI: https://doi.org/10.1007/BF00311954