I would like to get a second opinion on this dime. I think there is a small die crack on and above the eyebrow, and a die break near the edge of the mouth.
Its a CUD, I have a plastic 20 coin silver dollar roll full of them. theres few different commen ones, Teir drop is the most commen.
These are tiny die chips and blind-ended die cracks. They often develop on Roosevelt dimes on the eyebrow, corner of the mouth, and nostril.
Generally, CUDs are a die break that run from one part of the rim to another part of the rim. It happens when a piece of the die breaks off on the edge. What you see on the nickel is what's called a die chip. This is when part of the dies interior breaks off. They are usually very small.