Unlike man-made stones, water rather than oil is used on Japanese stones to prevent the surface from being clogged with metal particles. The coarse stones are 250, 800, 1000, and 1200 grit. The 250 and 800 grit are faster cutting and used for repairing nicked edges or reshaping a bevel. The 1000 or 1200 grit stones are used for the first stage of the actual sharpening to be followed by 4000 and perhaps 8000. Japanese water stones are softer than Western styles causing a fresh, sharp surface to be continually exposed to the tool edge but needing to be flattened regularly.
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