Very good scan.
Is there any chance some chip has been discolored/darkened by some external agent? Weather, chemical or whatever?
The $25s with white inserts are really strange, and the two couples of $100s are too similar shapes of yellow and orange...
Very interesting the 2 $1s, the darkest has a very brilliant blue.
Well this is sure enough work for Tom Stroh's next edition of PB guide.
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