Probably the simplest explanation would be holster wear; but could be from hanging on a peg for display, or resting the barrel on "something" when firing.

If it were a Mauser Broomhandle, I'd say it was from being carried in a wooden holster stock.

OK Eric... Bluing is an oxide layer on the surface of the steel. Its thickness in in the range of a few molecules. Abrasion will remove it. A grinding wheel would be one extreme of abrading away the finish layer, but it will happen eventually if the pistol is rubbed on anything often enough. If you can remember rubbing a penny on the carpet when you were a kid to shine it up, it's basically the same thing. The bluing on the grip straps is handled over and over, and simply wears away where it's repeatedly contacted. Dirty hands and their perspiration will take their toll. Inserting and removing a pistol from a holster, however soft, will do the same thing wherever the holster is rubbed by the gun on its way in and out. Voila! Holster wear! It happens mostly on the high spots and corners because they stick out the farthest and are the first areas rubbed. If we extend this thought to the elevated, "upset" steel pushed up and out from under a die hammered into the surface, it is obvious that its peaks are susceptible to bluing loss simply because they stick up a little bit compared to the surrounding, undisturbed surface. I hope this is a satisfactory and coherent explanation...

While everybody else was typing, I penned a brief description, for Eric...and beyond. It took a little time, as Don has pointed out, to craft the piece, try not to forget obvious details, etc. to make it clear and accessible. I was also thinking about comparing bluing loss with halos, but decided to keep it simple rather than explain halos, too, particularly since we explored that topic thoroughly not too long ago.

Although it might be possible to "go to the well once too often," my impression is that we will do the best we can in most cases, even if it only happens to be to suggest reading the FAQ or running a search. That's part of what makes this forum the best.

Dave , Thank you for your patience and common sense approach. Your explanations are priceless. Your thoughts shall be shared by all. You and Don are my heros to which I will always be there for you if needed! God Bless! You do more to heal me than any doctor or drug!! Our FAQ is priceless!! http://www.lugerforum.com/ Under General Information Section Just noticed Ed updated May 16, 2017~

David, thanks for your coherent explanation.

Gun steel is softer than we probably would like to think...

Halos are also caused when the blued steel surface is stressed and physically moved as the die plows into the steel displacing the metal structure around the places the die pushes into.

As the blued surface is plowed, the very thin areas spread apart in the process look lighter because the silver steel is pushed to the surface making the blued magnetite (the black oxide state of iron) thinner.

Those high spots are also more subject to abrasion wear, as David says above.

Should the numbers on the barrel have halos? That probably is most dependent upon whether the barrel is blued before or after the digits are stamped into the surface with the dies. Stamp the metal, then blue it and the bluing will be uniform. Blue it before you stamp it and you'll get halos.

It's probably possible to crudely fake halos by lightly applying chemicals that destroy bluing like "Iron Out" or "Naval Jelly". if that has been done, only very close examination of the area will help you determine if the bluing is real or faked.

blah, blah - either you live with Eric as he is or you don't! I have seen Eric go from barely able to write and he does well now. If he gets out of bounds, then we tell him.

In reality all these hundreds of words, you guys who wrote it could have told Eric and it would be over!

1. What lugers have halo's?
a. those made before salt bluing
b. markings before bluing
2. what is halo's - banging of the metal to other metal and it causes an indentation that spreads the metal, in short, it makes a halo

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personally I have seen good halos on the oddest lugers and other times, very nice looking pre-1937 (??) have almost no halo's. simsons seem to have lousy halos... why? unsure

Eric,
Early 1906 Navies, the no suffix block, do not show halos. ALL later Imperial Navies have haloed barrel serial numbers. 1908 Navies like your #2505b, as I've told you several times in the past, should show distinct halos, if they don't, they've been refinished.
Norman

Thank you all, I'm so sorry!!!!!!!!!!!!!!!!!!! At least I'm improving. My short term memory loss is forever permanent because of a subdural hematoma!! Ed, for many years you have been my forum guardian angel. Thank you for working with me!!!!

Ed,
what you write is true , but way short of comprehensive.
It is way too simple for such a complicated subject.

There, you "good deed" is now punished!:evilgrin:

And that has what to do with this subject being discussed?

Wrong location~