More like a die crack : check it : Die crack — A die crack is one of the most common die defects. It appears as a raised line across the coin — most commonly in the form of what looks like a crack on the coin. Die chip — Die chips are small, isolated chunks of metal that break away from the die, usually in the middle of the coin away from the rim. A die chip on a coin appears as a raised mound of metal, and these die chips can range in size from very small to quite large. Most die chips are less than 1 millimeter in size. As die chips grow beyond 1 to 2 millimeters, many error coin experts classify the chip as an interior die break .
I don't think that's a die chip. More like a weird Lamination issue. Many wartime nickels have lam issues.
There would be a raised area between the N and U of UNUM if it were any kind of Die Break or Crack That's more like a Planchet issue.
A Lamination would be more like it. Years of environmental toning caused an outline of the area in question.
A die crack would be thin and raised. That looks like more of a strange lamination error or a defect in them planchet. Nice find.
