Nitriding is a thermo chemical process by which the surface of a ferrous metal is enriched with nitrogen to improve the wear and corrosion resistance of components. Three nitriding methods can be used: salt bath nitrocarburising, nitriding and nitrocarburising in gas or plasma. Nitriding and nitrocarburising result in the formation of a very hard surface consisting of the compound layer and the diffusion zone. Metallography of nitrided layers is mainly used for quality control, controlling the nitriding process and for failure analysis. The main problems when preparing nitride layers are rounded edges and cracking or chipping of the layer during grinding and polishing. By carefully wrapping the sample in a thin copper foil before hot compression mounting, this problem can be overcome. For fine grinding silicon carbide paper or diamond on a fine grinding disc can be used, whereby the latter results in a better edge retention. The subsequent diamond polishing needs to be carried out as long as needed to remove any damage in the layer introduced by the preparation.