Another blood pitting

[Dwight Gruber]

I will postulate:

that blood carries a -much- higher concentration of oxygen than H2O, as haemoglobin is an oxygen fixitive;

that blood will pool and remain in a much higher concentration than water because of its coagulative qualities (thank you Big Norm) and because it does not evaporate, but rather, dries;

that blood has a "head start" on a blued steel surface because that surface is oxidized (the bluing process) to start with.

Assuming that "blood pitting" is a real phenomenon, does it operate differently on a rust-blued surface than it does on a salt-blued surface? Is the oxide-blued surface somehow catalytic?

--Dwight