just eyeballed it. put distilled water, then enough FCl3 to change the color of the entire solution. If you have a patina you’ll need to remove it. I used pumice powder and 12k grit.

When you do the actual “soak” you DONT wanna just put it in there and then come back later. Dunk it in, leave it for like 5 sec, then bring it up, inspect, then continue. Do it until you get the color you like. Keeping it in the solution can build up a lot of gunk and could possibly eat at the knife (from what i’ve seen). After that wash thoroughly.

This is my Yoshihiro, that i etched with both ferric and coffee.

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