I found this on
http://www.error-ref.comQuote:
Blanking burr (a.k.a, rolling fold)
Definition: A blanking burr forms when a blanking die or a hole in the perforated base plate is chipped. When a blank is punched out, a vertical burr is produced. When the blank is sent through the upset mill, the burr is folded over onto the planchet. The burr is eventually struck into the planchet.
A blanking burr appears as a low, broad, symmetrical tongue of metal that extends a short distance into the field. It is demarcated internally by a well-developed fissure. The edge of the coin is not disturbed.
Shown below is a 1967 quarter with a blanking burr in the southwest quadrant of the obverse face. At least three specimens are known with the same blanking burr. Naturally, the burr occupies a different location in each specimen.
The examples they show have don't have the burr still attached.
ANA ID: 3203813 - CONECA ID: N-5637 Clean a coin that may be worth collecting? Please DON'T! When in doubt, leave it dirty!!
