Is This A Scratch Or A Crack On This 2021 P Nickel?

Neither it is a ding.
John1

I'm new but like the OP if I saw that I'm thinking die scratch or something. What gives it away that it's from something else?

The difference? A die scratch is a line/void on the die. The dies are negatives. The coins are positives. Take a piece of aluminum foil and use the shiny side to press down on a coin. Press down the foil hard with the coin on the hard surface with your fingers. With the shiny side up, you see a copy of a coin. Flip the foil over and view the dull side of the foil. that is what a die looks like. (except for the rims. The rims are made by a step down area on the die called a gutter.
So with this information, you will note, that void on a die will make a raised area on the coin. Also everything on the dull side of the foil is mirrored. So in a die scratch, there would be the void copy of a scratch just on the fields areas.


The devices and designs are deeper into the die. So they will not usually be affected by die scratches. When you have a die chip/crack/break/cud, there is a new void on the die.


Note the crack? That creates the void that you see on die scratches.
Will the voids will be raised on the coin. Incuse on the die makes raised areas on the coins.
Not back to the original image. Is that area raised on incuse? It is incuse, so it is damage to coin, not a die issue. This happened after the strike. Not a die issue. Keep in mind that 99% of incuse marks on a coin are post strike damage. Only about 1% are mint errors. So when you see an incuse area on the coin, it should come to mind that is is probably a coin damage issue. If it were a die crack it would a raised area on the fields. Die chips can happen anywhere on the coin. So they will be raised on the fields or devices on the coin. So know what the die looks like, helps to understand how coins can be struck/damaged during circulation. Hope this helps. Include images of your projects so others will see what I'm taking about.