+1. if you go carbon in an environment it's going to get exposed to moisture much less liquid water, force the patina somehow. It can be as simple as the first use being some meat and acidic produce, then letting it sit a bit before washing. By a bit I mean twenty minutes or so, dry but not cleaned. I have a kitchen knife I made myself that got used for some thick onions, meat, peppers... then I lightly wiped off the excess moisture with a paper towel and left it on the cutting board while I cooked for a half hour. Then I washed it. That gave a mild but distinct patina that's kept it fairly safe from rusting quickly if a stray drop of water sits on it for a bit. Of course, the patina continues to develop as I use the knife, and because I did it the way I did the tang isn't protected. I handle that by wax for the most part.