Crystallographic Orientation of Clinoenstatite Produced by Deformation of Orthoenstatite

Science  06 Apr 1973:
Vol. 180, Issue 4081, pp. 64-66
DOI: 10.1126/science.180.4081.64


Uniaxial compression at 800°C and 5 kilobars confining pressure of a specimen cored from a single crystal of orthoenstatite [(Mg,Fe)SiO3] produced fine lamellae 100 to 1000 angstroms thick of untwinned clinoenstatite. The two phases are joined along (100) planes and have b and c axes in common. The orientation of the clinoenstatite a axis contradicts several previously suggested transformation mechanisms and reduces the set of possible mechanisms by a factor of 2.