Our Scythe Outfits ship with a man made stone, and plastic stone holder. The holder is filled with water to keep the stone pores free of debris. We also have several different peening systems that are used to draw the edge of the blade out after the edge has been sharpened many times. The manmade stone is used after peening (new blades are already peened, but not sharp). It gives a good edge, but for grass mowing - you'll want the natural stone also. The Natural stone is similar in hardness to an American 'arkansas black', and gives a surgical sharp razor edge. It is used in the field after 10-15 minutes of mowing, when you feel the blade start 'pulling' instead of 'slicing'.