42 BYF question

[DonVoigt]

Originally Posted by 4 Scale

I have found a stereo microscope is the ultimate tool for diagnosing re-blue. Typically local jewelers will let you use theirs to inspect an item although of course it helps if they already know you.

I have a stereo microscope, and I can tell you that all Lugers, even high-condition ones, have rust (pitting). On a high condition gun the pits are not visible without magnification but they are there. It is a question of degree. If it's a re-blue you can see rust in the base of the pits.

Yes, on any before 1937 for sure-
that is why they call it "rust blue".