Looks like a possible lamination streak. ....from improper metal mixture of the planchet strip in that area.
I used to have streaks similar to that on my silver dollars. I used to store them in the old PVC flips and had a rubber band around them to keep them together. The outside ones had distinctive lines like that one them. One of my recent threads I cleaned the dollar coins to remove the streaks. Not sure if it's the same thing being seen here.
I actually had that 'rubber band' possibility written at the end of my post, but I wasn't sure, based on the photos, so i deleted it. I agree it's a very distinct possibility, difficult to know for such which it is, from these photos.
I actually discussed it here on my 1922 Peace Dollars https://www.cointalk.com/threads/1922-peace.310925/#post-2992473
Looking back through records, it only took about 2 years for my 1922s to get a more distinctive strip like that via a rubber band. I found inventory pics from a couple years ago before I put rubber bands around them to keep all my peace dollars together. Before pics they had normal silver tarnish. Then a few months ago had fugly black strips on them from the rubber band.
Makes a ton of sense to me now that you say it! Thanks for the notes. You say that you cleaned the coins??? How did you clean them properly???
That's a loaded question. I was taught how by members on this site and wading through stuff on the internet (keep in mind I did jeweler stuff in the past so I was able to think of how to improve it and throw away stuff on the internet that I knew would create damage). The linked thread was my first Dollar coin though, and I over did the cleaning on it - they're so pretty when they are shiny though . Since I have not perfected it to something better I'd rather not say as I don't want to give you instruction and then you to damage your nice examples. You may want to start a thread of how you can "conserve / clean" your particular Peace Dollars and get info from the experts.
