The proper term is ridge ring with it rises up almost as tall as the devices:
No premium for this. Happened a lot on the 1980's zincolns. Show showing up on the reverses now that they change the hammer and anvil locations for the dies. (used to be the heads was the hammer die, and the reverse was the anvil die. Now they have changed just opposite)
@Guerr113 The wear is on the die, not the coin. It's just how coins struck by an older die will look as the metal of the die begins to deteriorate. It doesn't add any value, but it is interesting to see one on a shield cent. You mostly see them on mid to late 80s memorial cents when they really used to run the dies into the ground.