Japanese water stones provide you with a tried and true, time-honored method of sharpening your knife, sword or other cutlery blades. These traditional sharpening implements boast several advantages over harder stones, including resistance to becoming glazed or loaded with the material they are sharpening. New particles are constantly exposed as you work the knife, so the stone continues to cut consistently. Water stones can be effectively lubricated with water, so nothing but water is required! And because water stones are soft, the worn material and the water form a slurry that - in conjunction with the stone - sharpens and polishes the blade.