Genuine, natural Arkansas stones are the only stones in the world that polish your cutting edges as they sharpen. This stone offers a different grade on each side; one side is a Dunston black (extra-fine density) Arkansas stone, the other is a translucent (ultra extra-fine density) Arkansas stone. The Dunston black grade (dark-gray in color) is ideal for achieving a fine, polished edge. The translucent grade (white with marble-like streaks of pink, yellow and/or gray) is the rarest of Arkansas stones, ideal for achieving highly polished razor's-edge sharpness. Arkansas stones are great for use on gravers, knives and other cutting tools.