No, I haven't blued it, that's just whatever is under the coating. Someone on BF was saying it's decarb?
Correct..standard SR-101 look under the coating.
Question: Is that a Hamon line? You mentioned the knife hadn't been used to chop as of the initial pictures....it looks like there's a bit of a heat treat difference between the blade edge and the spine of the blade. Could you take some closer pictures along the length of the edge highlighting that variation? If you can tell, is it inherent to the metal, or is that a patina caused by cutting something else? Any feedback would be great. If you confirm it was already there, and you did not apply it in some fashion.....I may have to strip mine just for principle...and see if it also has the same.