I've been using DMT products since the 80's. These 8" dia-sharps are my mainstay. After burglary, they're fairly graded and simply don't require maintenance of other stones. If you have a range (after medium-extra-fine, I have everything), you can use 4000 (6 microns) There has been a hole in this line for some time, nice to see it has been filled. sharp meaning the gradation is lower (coarser) than advertised. The stones wear down with use and I actually break them before I use them for anything significant. To break up and clean these stones, spray them with a solution of Plain Greens and a water. Use this as a stone lubricant all the time, it just works better than water or dry Take a hardened (ok if it's the width of the stone) piece of 440C (I use an old knife shank) and run it up and down in a circle or something but try to cover the whole area she keep adding. Simply green as needed, rub the stone and steel f when it gets dirty (it will) and you should feel the stone smooth out. There are small dirt particles and manufacturing eccentrics in the coating they put on it and you need to clean that up. Once this is off, the stone will have a much more even texture than you would expect. At the moment when the surface is even, the stone is still slightly rough, but becomes smoother with use. Keep using the Simple Green solution to keep the stone and work clean. When breaking in, take extra care to finish the edges of the stone, this is important as this area can be slightly rough. Beveling the edges with the Dia-Lap 120 doesn't work very well either. If you have a stone that is not coated to the brim, do not return it; I want them to make them like this. The stone should have a uniform gray-silver appearance when properly cleaned and impacted.