Norton water stones have an aluminum oxide abrasive held by a relatively weak bond that releases fresh particles at a fast rate. In our tests, they were comparable to King stones when sharpening O1 steel, but in tough alloys such as A2 and M2 they cut approximately 40% faster than King. Because of the steady release of fresh abrasive, they produce a consistent scratch pattern at each grit, making it important to work through the grits progressively to obtain a final polish.