I don't know what these are

[minidisc0]

Maybe you guys do.

Four coins here. Two have the same bubble thing below the steps and same die scratches. One looks like a die chip.

[1sgret]

Looks as though it may have been a air bubble that burst while the coin was being struck. It is hard to tell for sure.

[dvn]

Looks like die cracks and die dents to me. See what others have to say.

Billy (dvn)

[corroded]

Dribbles and globs!!!!

[mikediamond]

Die cracks, die chips, and perhaps die damage. The curved line is unusual for a simple die crack.

[minidisc0]

might be hard to see in the pictures but the curved line has some elevation in it leading up to the stairs - like a large bubble.

[mikediamond]

Then the curved line could be the edge of a die dent that promoted cracking along that border. Alternatively, it could be an incipient retained interior die break, but these don't usually bulge in the manner that this one appears to.