Like a wayward comet, some minting mishaps appear suddenly and
disappear quickly, never to return. They can even be quite common in
the short period they’re with us.
Undoubtedly the briefest burst of activity recorded for a unique
minting mishap is the emergence and disappearance of “ejection impact
doubling” or EID. This phenomenon is restricted to Sacagawea dollars
produced in the year 2000. All but one example are from the
Philadelphia Mint and at least six different die pairs are represented
among a subsample of 12 coins I examined for this purpose. These and
hundreds of additional pieces were accumulated by small dollar
collector Mike Clements.
Not a ‘Mint error’
I’ve intentionally used the phrase “minting mishap” because
ejection impact doubling is not technically a “Mint error.” Although
it arises from direct contact between coin and die, it occurs after
the strike has been completed as a newly-struck coin is violently
propelled into the face of the retreating hammer (obverse) die.
Ejection impact doubling leaves a few scattered die-struck design
elements on the obverse face, the most recognizable of which is the
disembodied iris and pupil from Sacagawea’s left eye (to viewer’s
right, see photos).
The extra eye is usually located between Sacagawea’s eyebrows or
along the bridge of her nose. However, it has been found as far away
as her cheek. Double impressions of her right eye have also been
observed (see photos).
When ejection impact doubling was first discussed in this column
(Aug. 1 and 29, 2005), experts disagreed over whether it was merely a
form of machine doubling or was, in fact, a novel form of post-strike
design transfer. Machine doubling occurs immediately after the hammer
die has reached the lowest point of its downstroke. The hammer die
sometimes drags itself horizontally through the newly-struck design,
smearing it to produce “slide doubling” (Collectors’ Clearinghouse,
Sept. 13, 2010).
Bounces, shifts or rotates
On other occasions, the hammer die bounces up, shifts laterally or
rotates, and then lands lightly on the newly-struck design. Referred
to as “push doubling,” this second form produces marginal shelving
along the edges of affected design elements (Collectors’
Clearinghouse, March 15, 2010).
In the third and rarest form of machine doubling, the die bounces
unusually high, shifts laterally (sometimes with a slight rotation)
and lands lightly on the design rim, leaving an extra set of
peripheral design elements. This subtype is designated “one-sided,
rim-restricted design duplication” (Collectors’ Clearinghouse, May 22, 2011).
It is clear that ejection impact doubling is entirely different in
cause and appearance from any form of machine doubling. The distance
between the extra eye and its normal counterpart is much greater than
any known example of machine doubling. Furthermore, the eye is
sometimes rotated as much as 90 degrees (see photo). When machine
doubling incorporates rotation of the hammer die, it never amounts to
more than 2 or 3 degrees.
As to why ejection impact doubling is restricted to this year and
this denomination, we may never know.
Experimentation at the Mint?
In the Bliss press commonly used in this time period, the anvil
die rides up and down on a cam. As it sinks down, the anvil die brings
a freshly inserted planchet down into the collar. As it comes up, it
pushes the newly-struck coin into the path of the ejection finger.
Perhaps there was an unusually energetic push from below by the anvil
die. However, since all Bliss presses operated in this fashion,
perhaps the Mint was experimenting with some other means of expelling
a tightly-fitting, newly-struck coin from the collar. Perhaps the
anvil die was fixed in position and it was the collar that moved up
Whatever the cause, it would seem that the coin flew into the face
of the hammer die, rather than being pushed into it. If the latter was
the case, one would expect to at least occasionally see transferred
design elements (or at least impact damage) on the reverse face. And
we never do.
Additional information and photos can be found in the
January/February 2005 issue of Errorscope, published by the
Combined Organizations of Error Collectors of America.
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