There were often color variations in salt blued Lugers like your byf 42.
The tone could shift to purple and lavender depending on the nickle content of the steel alloy, the chemical mix and the duration spent in the bluing baths.
Some of these late Lugers were assembled from spare parts at the end of the war by Mauser employees for direct sale to GIs that were passing through the area. They can show internal blued parts that are normally found in the white.
I have one like this early in the "G" block, and it looks like it did the day it left Mauser.
http://forum.lugerforum.com/showthre...er+banner+715g
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.