Burnishing is a finishing technique that involves rubbing a surface with a hard tool, such as a ball or roller, to compact the surface and achieve a smooth and shiny finish). Burnishing can be used on various materials, including metal and wood, and can improve surface finish, increase hardness, and improve fatigue life. Burnishing is a cold working process that produces a super fine surface when hardened rollers are moved on the surface of the material. Burnishing can be carried out in a number of different ways, including using a dedicated machine or a regular lathe or milling machine. Burnishing can also be done by rubbing two pieces of wood together or rubbing small shavings or chips on the wood. While burnishing can have desirable effects when done in a controlled manner, it is normally undesirable in mechanical components because it can alter the surface finish of a part and its effects can be unpredictable).