Diversity of the Structure of Diamond Crystals and Aggregates: Electron Backscatter Diffraction Data

Abstract

Diamond crystals of various morphological types, including carbonado, were studied by the electron backscatter diffraction method. Cases of inhomogeneities of different natures were revealed: interpenetrant and mechanical twins, incoherent intergrowth, and splitting growth. Differences in the distribution pattern of boundary angles for different types of inhomogeneities have been shown: predominantly discrete in intergrowths, continuous distribution of low-angle boundaries in ballas diamonds, and continuous random distribution in carbonado. It has been shown that Rose channels in diamond arise as a result of etching at the intersection of mechanical twins. The revealed mechanical twins have a thickness of 60–600 nm.