Part V. Planchet Errors:
Blanking and Cutting Errors:
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.
Depicted below is a 1972-D nickel with a blanking burr in the northwest quadrant of the reverse face.
Image courtesy of Heritage Auctions.