The 20th and 21st centuries are studded with numerous spikes (and
drops) in the production of specific error types. These spikes affect
numerous categories of die, planchet and striking errors.
Some surges in striking errors are easily explained. The year 1966
produced numerous rotated die errors (mostly 90 degrees) among
Jefferson 5-cent coins. The vast majority can be traced to a single
This same year brought us a less easily explained rash of Lincoln
cents struck by horizontally misaligned obverse (hammer) dies. The
misalignments are unusually severe, and head off in several different
directions (see photo of 1966 Lincoln cent).
Lining up a quartet such errors, I was unable to match up the
patterns of die scratches. Each coin was clearly struck by a different
die pair; how many different presses were involved cannot be ascertained.
Equally puzzling is the failure to see a similar error pattern in
other denominations struck in 1966. Except for some rare instances,
coinage presses are not dedicated to a specific denomination. Once the
production totals for one denomination have been satisfied, the dies,
collar and feeder assembly are changed to accommodate a different denomination.
Error production patterns confined to a single denomination are
actually quite common and can stretch over several years.
In the July 12, 2010, “Clearinghouse” column, I reported on a
nine-year run of Lincoln cents with faint, oddly positioned clash
marks (see photo of 1996 cent here).
The clashes all occurred when the hammer die was tilted and
horizontally misaligned to a remarkable degree — up to 50 percent.
They’re so different from ordinary clash marks that it seems likely
the mishaps occurred during installation rather than during a press
run. Restricted to the years 1992 to 2000, the current count is 19 die
pairs. Again, it’s unclear why the same mishap failed to occur when
these presses were switched to other denominations.
An error production pattern can even be confined to a single
design subtype. In the Jan. 3 “Collectors’ Clearinghouse,” I reported
on research conducted by Robert “BJ” Neff on tilted die clashes found
in 1960-D Lincoln, Small Date cents (and one 1960 Small Date cent). An
example of the 1960-D cent is shown here.
A tilted die clash occurs when the hammer die makes direct contact
with the anvil die at an angle, leaving a set of reciprocal clash
marks at one pole on each die. Such clashes are quite rare — except in
At the time of writing, 35 such clashes have been cataloged, with
at least 15 waiting in the wings for cataloging.
While examining more than 5,000 Small Date cents from both the
Philadelphia and Denver Mints, Neff noticed some other intriguing
patterns. Not a single conventional die clash (which produce the
familiar “Lincoln in jail” effect) was found. Many of the dies from
both Mints were covered by heavy die scratches, regardless of whether
clash marks were visible. Die scratches are the product of intentional
die abrasion, performed to remove clash marks and other types of
Neff also detected a high frequency of “conflicting dies”
(switch-outs). These examples show clash marks on only one face; the
opposite die was replaced before the press was restarted.
Neff thinks that the presses responsible for the tilted die
clashes and other effects were plagued by a number of problems: 1)
difficulty in maintaining a horizontally oriented hammer die face, 2)
difficulty in maintaining the minimum die clearance necessary to
prevent a clash in the case of a planchet misfeed, and 3) an
abnormally high rate of complete planchet misfeeds.
Neff thinks it’s possible that a different kind of press was used,
or that a standard press was modified for the production of these
Small Date cents. Whatever the changes, they didn’t work out very well
and the experiment was abandoned.
Neff’s scenario only works if we surmise that the novel press
design was used strictly for the small date cents. It also raises the
question of why the cent design was modified after the experimental
presses were abandoned. Conjecture aside, his evidence at least calls
into question the standard explanation for the switch to the Large
Date subtype — a propensity for die chips to develop in digits of the
Further details of Neff’s investigations can be found at www.maddieclashes.com.
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