That would be a "Die Chip". Common on Nickels. Jefferson Nickel; 1938 – Present : Cuds on Coins (cuds-on-coins.com)
@ARBIE SANTOS . Where do you think there is an Error? I see a Damaged digit 6 and Rim damage. Also, a "die chip" in the Number 4 possibly.
A whole lot of damage, might be a die chip inside the 4 but it's hard to tell could also just be from the poor quality of the coin
Your first coin has an internal die break, although minor and doesn't command much, if any, premium. I see what you are referring to on the second coin, but I believe it is just circulation damage and not doubling. JMHO