Stellite 6K is not a steel — it's a cobalt-chromium alloy, and that distinction matters. Without iron in the matrix, Stellite is essentially immune to rust in virtually any environment, fresh or salt water included. It will never pit, never stain, and requires no maintenance to preserve its corrosion resistance. The tradeoff is that it's extraordinarily difficult to work: it cannot be heat treated in the traditional sense, it defeats conventional grinding wheels, and sharpening requires diamond abrasives. Tom Mayo has made Stellite 6K his signature material, and his mastery of the alloy is recognized as among the most technically demanding work being done in the custom knife world today. These are genuinely rare pieces.