Came across a post where person finds 52100 (ZK) more reactive than a knife in White steel #2 (I presume that it was a monosteel knife like Masamoto KS).
That's interesting, as on paper, White steels have no chromium at all, while 52100 has 1.5%, not a lot, but 3 to 5 times as much as Hitachi Blue steels. I find that if I leave a knife slightly wet overnight, it will discolor, but won't rust. I mostly see rust when I grind, while the scratches are deep, or sometimes when handle opening allows water, so there is a regularly exposure to water on the tang or right around tang opening.
Not sure how to interpret this. Suggestions?
Polish might have a hand in this, but I haven't seen high polished white steels J. knives with exceptions of honyaki knives.