I found a small printing error on some CDB notes, so the large numeral on the back looks like a 1,0 (instead 10) See the scan.
The plate number is 32 (serial 8975100-199) and the error was found on about one every three notes. Is anybody have already found the same error?
What you have found is a hickey. There has been an article written on this occurrence and the reason it occurs every third note or so in a CPMS journal.
I have found several $10 -150 notes with this occurring around the same region.
While you see it as a "comma" between the 1 and 0 I took it as an extra flicker of light through the trees. I will try to scan and put up a picture.