An examination of polished diamond surfaces in the electron microscope

Micrographs of polished diamond surfaces show that even well polished surfaces are rough on a microscopic scale, with height variations of the order of 5 nm over distances of the same order. The geometric structure of this roughness is not fully resolved but clearly depends on the crystallographic orientation of the polished surfaces. This unusual topography arises from the exceptionally brittle nature of diamond, and correlates with the unusual properties observed in other experiments on the abrasion resistance and friction of diamond.