Yes - I also have Mauser made Lugers from WW-II that show the plum colors.
A few years ago, I got a couple of Bavarian / Austrian re-issued M1 Carbines that show the deepest plum coloring of any metal I have. These were redone sometime after the end of WW-II through the 1960s.....
Here's a quick picture:
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.