Some old spray paint residue that was applied just on the Reverse. I don't think it could be any issue with the Planchet since that year was not plated.
Thanks for the replys. I know it's not glue or cement. It's shiny and definitely looks like metal and is thicker and stronger than what spray paint would be. Did they make metallic spray paint 60 years ago? This penny has been in a family collection, stored in a safe for many, many years. I know that it hasn't been tampered with at any time in recent years. It would have had to be a long time ago. We have a few others with this same thing going on. If they weren't plated during that year then maybe someone tried to plate it themselves after mint. I'm just so curious what it really is. I know that it's worth only 1 cent but it's still kinda neat.
Thank you. The camera I'm using isn't as good as my other one but it's out of commission at the moment.