Abstract Conventional grinding methods are harsh and produce dramatic changes in coal. When coal, initially at room temperature, is ground in the presence of air, the high localized temperatures produced are known to cause both the production of gases and surface oxidation. These perturbations make meaningful measurements on the product very difficult. A technique that minimizes these effects is the pulverization of coal in liquid nitrogen. Compared with conventional methods, the process is rapid and appears to be less destructive chemically. Electron Spectroscopy for Chemical Analysis (ESCA) measurements support this conclusion. Surface oxidation is significantly reduced by this mild treatment. The method produces more particles below 38 μm than does conventional grinding and these fine particles are less prone to agglomeration.