I do not believe it to be glue as the area in question seems to be under the lettering also. There are many anomalies on post 1983 cents, but this appears to be a lamination or alloy deterioration issue. Wait to see other's opinion on your coin. Very interesting thanks for sharing it good luck.
Almost looks like it was the ender in a roll and the paper crimp caused an acid reaction to cause it to look like that.
You like giving me a hard time? Lol! I will find something in these jars lol. No it does not seem like glue at all. Thank you though!
Thank you. I agree it does not look or feel like a substance on it. I do see some corrosion but the rim is puzzling. Thanks again.
Whatever it is it appears to be under the letters. That makes me think the copper plating was applied to the Zinc and it didn’t adhere correctly. Set aside and look again later. Hehehe-Could it be the heat and humidity in Louisiana? Hehehe