Stonewash, Satin or DLC: What Each Blade Finish Does
A one-line question about favourite blade finishes produced the kind of thread that is more informative than a marketing page. The original poster named stonewash, and the replies split between stonewash, hand-and-belt satin, and the extravagant end of mirror-polished DLC.
Finish is not decoration, it is a maintenance strategy. A stonewashed blade is tumbled in ceramic media until the surface becomes a random pattern of shallow dents, and those dents hide the scratches that accumulate from use. That is why it is the default on working knives: a scratched stonewash looks the same as a new one from a foot away. A satin finish, especially a hand-rubbed one, is a series of directional scratches that shows every new mark, which is why it appears mostly on knives that are bought for their looks.
DLC goes the other way. A diamond-like carbon coating is hard, thin and slick, and it protects the steel underneath from the light surface wear that dulls a polished blade, at the cost of a finish that can show wear as a lighter scuff where the coating is abraded. Mirror-polished DLC, as one reply described, is the most unforgiving combination: a reflective coating on a polished surface, where any mark is visible from across the room.
The reply that mattered most was the shortest: it depends on how the knife is going to be used. A knife that rides in a pocket with keys wants stonewash. A knife that gets cleaned and photographed wants satin. A knife that lives in salt water or a humid environment benefits from a coating for corrosion resistance rather than for looks, and that is the only functional argument for DLC that survives scrutiny.
The verdict is to pick the finish last, after the blade geometry and steel. If you use a knife hard, choose stonewash and stop thinking about it. If you buy for the look, buy the finish you like and accept the maintenance. What you should not do is pay a premium for a cosmetic finish on a knife you intend to cut cardboard with, because the first week of real use will erase the difference.