Contrary to suspicions occasionally voiced by novice collectors,
most minting errors are purely accidental. But there’s no denying that
some errors have gotten a human assist somewhere along the way.
“Assisted errors” are those that had help in either their
production or their release from the Mint (or both). Error coins
created expressly for the hobby trade can be termed “intentional errors.”
It’s not always easy to distinguish assisted and intentional
errors from those that arise by accident. The key to discriminating
between these two populations lies in an informed assessment of
pattern and process. Does the coin violate the constraints imposed by
the minting process? Is the sequence of events so improbable as to
beggar the imagination? Do relative abundance, raw abundance and the
presence of unexplained spikes of highly unusual errors point to human intervention?
It is generally acknowledged than any oversized or misshapen Proof
coin had help getting out of the Mint. Proof coins are only released
in Proof sets sealed in plastic. Each coin occupies a tightly-fitting
hole in a common mounting plate. A coin unable to fit into its
respective hole could not have been released in a Proof set. While
some of these Proof errors may have been made-to-order, others are
probably accidental products of press malfunction. It’s the manner of
their release which marks them as assisted errors.
Some errors impossible
Some errors are considered impossibilities from the standpoint of
normal press function and design. A planchet or coin struck with a
design intended for a smaller denomination has traditionally been
considered a “forbidden” error. An oversized coin or planchet could
not fit into the feeder tube or feeder finger and therefore could not
be fed into the striking chamber.
Illustrating this “forbidden” error type is a 1977 Canadian 5-cent
coin struck a second time by 1978 cent dies.
I’m not fully convinced that all such errors are impossible. After
all, such an error can be produced accidentally if press operators
fail to change the feeder assembly when switching dies from a larger
to a smaller denomination. A coin left in a hopper or conveyor from
the earlier press run could then make its way to the striking chamber unassisted.
Even so, I’m quite confident that the Canadian coin is an
intentional error. Two different dates on an already improbable error
are a bit hard to swallow. More importantly, the year 1978 produced a
bumper crop of cent designs struck on larger planchets and coins, far
too many to be accidental. I’ve heard from several independent sources
that the Royal Canadian Mint actually set up a cent press that would
strike visitors’ coins at the end of their tours of the RCM facility.
In 1981 the Philadelphia Mint produced its own rash of similar
errors. They include a Lincoln cent struck on a 5-cent planchet, a
cent design struck over an Anthony dollar and a dime design struck
over a cent die cap. In each case, only the obverse is die-struck. All
of these errors are uniface — struck against an underlying planchet.
Sometimes a coin is so bizarre that it is impossible to conceive
of it as an accident. A prime example is the illustrated undated dime,
which was struck slightly off-center on a burnished Proof planchet. A
small circle of die-struck design occupies the center of the reverse
face. It was delivered by a circulation-quality (“business strike”)
die. The die-struck circle lies opposite a deep pit on the obverse
face. Whatever object generated this pit provided the resistance
necessary for the reverse die to leave an impression. Elsewhere on the
dime there is no trace of die contact on either face. It therefore
would seem to be a unique manifestation of an “invisible strike.”
An invisible strike occurs when the dies are too far apart at
their closest approach to leave any design on the planchet. However,
when another planchet, a previously struck coin or a foreign object
intrudes into the striking chamber, it takes up the excess space
between the dies and permits an area of die-struck design to form
opposite the respective brockage, indent or struck-through error (see
Collectors’ Clearinghouse May 3, 2010, and Sept. 20, 2010).
The pit is bowl-shaped in cross-section and carries a peculiar
knurled texture. The right side of the pit appears to show a brockage
(incuse mirror image) of the lower of the two acorns that adorn the
This coin invites rampant speculation concerning its nature and
origin, speculation that is given free reign in the November/December
2006 issue of Errorscope.
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