linclon penny 1991, error

[ariel cabrera]

Clips metálicos en la punta del monumento y en el borde, en las iniciales del grabador, o podría ser una duplicación.

[MintErrors]

In my opinion, it is called zinc plating issues. It happens with cents made of zinc. There was air trapped under the planchet when it was made. When the planchet was heated up, it swells, and causes these zinc blisters. It is more common on zinc coins from the 1980s.

[ariel cabrera]

In my opinion, it is called zinc plating issues. It happens with cents made of zinc. There was air trapped under the planchet when it was made. When the planchet was heated up, it swells, and causes these zinc blisters. It is more common on zinc coins from the 1980s.

I have already tried to exploit them and it is pure metal.

[MintErrors]

Yes, it is still metal, but it had air under the metal.
Google can help:
https://coinauctionshelp.com/bubble-...%20and%20sizes.