The HOPG is used as monochromating or diffraction material for X-rays and neutrons. It is well appreciated also providing surface microscopists with a renewableand smooth surface. Unlike mica, HOPG is completely non-polar and, for samples where elemental analysis will also be done, it provides a background with only carbon in the elemental signature. The extreme smoothness of HOP Gmakes results in a featureless background, except of course, at atomic levels of resolution.