[Maestro]

Originally Posted by cirelaw

The answers are right here! http://www.lugerforum.com/FAQ.html A must read for all~~ Thanks to Ted!!

Q: What is the difference between hot Salt (dip) bluing and rust bluing?
A: The differences can be seen in the interior (in the white or blued) and is a by product of the nature of
the different bluing methodologies. In rust bluing, the bluing solution is painted on the surface to be blued,
and the part is then hung in a steam cabinet. The area of the piece painted with the bluing solution literally rusts.
When removed from the steam cabinet, the painted area is bright red with rust. This area is then carded
to remove the red rust, leaving a blued finish. If a deeper blue is desired, the entire process is repeated.
Since only the area one wishes to be blued is painted with the bluing solution, only that area ends up blued.


(Photos courtesy Ted Green)

In hot salt (sometimes called "dip") bluing, the entire part is dipped into a tank containing the bluing solution.
It is left to soak for a specific period of time, removed, the bluing solution still on the piece is neutralized,
and the part is oiled to stop the bluing process. Rust blue is a more durable finish, but a labor intensive finish.
Salt blue is less durable, but also less labor intensive. Anyway, that's why the inside surfaces of a rust blued
piece are in the white and the inside surfaces of a salt blued piece are blued. This is also one definitive way
to tell if an Imperial Luger has been reblued. If the inside of the frame is blued, it's a refinish. I hope this
helps!

Kyrie