Wiki-Finishing grindstone

It is one of the three types of grinding stones, the finest of which is used mainly for finishing work to clean up the appearance. In terms of synthetic whetstones, it generally refers to those with a grit size of #3000~. Because of its fine grain, the grinding and polishing power is low, but the scratches on the metal are shallow, resulting in a clean finish.

Related websites
Mastering Japanese Knife Sharpening: Techniques & Tips | KIREAJI