I need help as I am new to the coin collecting world I enjoy it and just want to know if anybody can tell me anything about this 1981 D penny
Meow has found a few like that too, and is not positive what causes that. Meow suspects tumbled in a dryer with other coins for a long time maybe.
Both coins are just damaged. The zinc was exposed on the 1990 and is corroding away. Hard to say exactly what happened to the 1981 but definitely has been damaged post minting.
No more pictures needed The Copper 1981 is damaged. Called a dryer coin as stated. The 1990 copper plated cent is damaged also. Exposed plating ate away at the zinc core. Environmental Damage. None are mint errors @l.cutler you beat me to the answer