Neither is a rolling fold. The dime appears to be post-strike damage, with metal from the edge having been relocated onto the design in the form of a thin apron. The nickel may represent the same thing, or it might be a lamination error.
It would be more accurately referred to as a blanking burr. It's a metal burr produced by a dull blanking die or a hole in the perforated base plate whose edge is dull. The burr is folded over during upset and is struck into the coin. It appears as a broad, symmetrical tongue of metal that extends a short way into the coin. It is always surrounded by a narrow fissure. The edge of the coin adjacent to the burr is completely normal. Rolling folds are rather rare, but not particularly valuable.
Thanks Mike. I understand the 'blanking burr', and it makes sense. I find quite a few of them. It's good to get the terminology down.
Most struck in burrs are "rim burrs". These are produced during or after upset, often just before the coin is struck. They generally take the shape of a sharp "fang". Rolling folds are rare and they take the form of a low, broad, symmetrical tongue. A rim burr is usually associated with damage on the edge. A rolling fold isn't.
