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Pre-Strike Damage
Closely Mimicking an Incomplete Punch
by Mike Damond
Some months back Frank Leone
sent me a 1980 cent with what
he suspected was an incomplete
punch (Fig. 1). An incomplete punch
(incomplete clip) occurs when the
punch (blanking die) fails to completely
penetrate the coin metal strip.
When a second, successful punch
overlaps the initial incomplete
punch, a blank is produced with a
curved groove on both faces. This
groove persists even after the coin is
struck.
At first, the planchet defect on
Frank’s coin does resemble an incomplete
punch. However, further inspection
showed that it was another form
of pre-strike damage that coincidentally
resembled a bona fide incomplete
punch.
Let’s compare Frank’s coin with an
undoubted incomplete punch. This
1996-D quarter shows both an
incomplete punch and a curved clip
(Fig. 2). An incomplete punch should
be present on both faces and the two
Errorscope, November/December 2008 . . . . . . page 30
punch marks should line up perfectly.
One punch mark is from the edge
of the blanking die. The other is from
the hole in the perforated base plate
that the blank is pushed through. The
quarter fits the expectation. However,
the 1980 cent shows a punch mark on
only the reverse face. The obverse
only shows a slight indentation in the
design rim at 3:00.
An incomplete punch should penetrate
the surface, which is indeed
what we see in both the 1996-D quar-
Figure 1a,b. 1980 cent with what looks like an incomplete punch on the reverse face
(but isn’t). Coin courtesy of Frank Leone.
Figure 1c. Close-up of the alleged
punch mark.
Figure 1d. Cent blank placed next to the alleged
punch mark. The radius of curvature of the cent
blank is much greater than that of the faux punch
mark.