Flash any error collector an image of an extensive, incuse
mirror-image and the first candidate explanation that comes to mind is
a brockage. A brockage is formed when a coin (or any piece of
die-struck, hard material) is driven into a planchet or another coin.
However, the incuse mirror-image on the reverse face of the
illustrated 1969-D Roosevelt dime is not a brockage. It is instead an
incuse ghost image.
This is a copper-nickel clad layer that either separated from an
off-center dime after the strike or that entered the striking chamber
on top of a normal dime planchet. While these two possibilities cannot
be disentangled, the effect on this exceedingly thin and lightweight
(0.37 gram) disc is the same. The side of the disc that was in direct
contact with the obverse die molded itself to the recesses of the die
face. The side that was in contact with the underlying planchet (or
that was loosely adherent to the copper core) also sank into the
recesses of the obverse die.
Any thin disc that enters the striking chamber together with
another planchet will obey the same principle. This is illustrated
here by an undated Lincoln cent that started out as a
split-before-strike planchet. Weighing 1.54 grams, it was inserted
into the striking chamber beneath another planchet. The resulting
in-collar uniface strike (full indent) left the coin with an incuse
ghost image of the Lincoln Memorial on the obverse face.
A similar-looking incuse Lincoln Memorial formed under somewhat
different circumstances in the double-struck 1977 Lincoln cent
presented here. This 1.58-gram example entered the striking chamber as
a rolled-thin or split-before-strike planchet. The first strike left
it with a die-struck design on both faces but no ghost image. The
second strike took place beneath a planchet. This flattened the
die-struck obverse design and generated the incuse ghost Lincoln Memorial.
A coin that is thinned by multiple strikes against a succession of
planchets will gradually develop a clear incuse ghost image. That’s
what happened to the multi-struck 1996 Lincoln cent shown here.
Weighing only 0.24 gram, its reverse face shows a mirror image of the
obverse design. This demi-coin is the detached bottom of a late-stage
obverse (hammer) die cap. The copper plating was completely worn away
as the cap’s working face struck a series of planchets. Detached cap
bottoms are often mistakenly assigned to an error type that doesn’t
even exist among copper-plated zinc cents — the “split-after-strike shell.”
A planchet or coin of normal thickness can also develop an incuse
ghost image if it receives an unusually strong off-center uniface
strike that reduces its final thickness to a fraction of its original
girth. Illustrating this phenomenon is a double-struck 1998 cent in
which the second strike was 60 percent off-center, with the obverse
face covered by a planchet. A strong incuse ghost image of the Lincoln
Memorial has formed on the obverse face.
Distinguishing an incuse ghost image from a brockage is usually
not too difficult. Most brockages show at least some expansion, while
a ghost image is never expanded. Fine details are muted or lost in a
ghost image, while they’re usually clear in an unexpanded,
first-strike brockage. In a ghost image, it is often the centrally
located, highest-relief portions of the design that are easiest to
recognize (they may, in fact, be the only recognizable elements). The
final factor to be considered is thickness. The thinner the metal, the
clearer the ghost image. Usually the opposite is true of brockages. A
planchet or coin thinned by the strike will generally show an expanded
and distorted brockage.
Coin World’s Collectors’ Clearinghouse department does
not accept coins or other items for examination without prior
permission from News Editor William T. Gibbs. Materials sent to
Clearinghouse without prior permission will be returned unexamined.
Please address all Clearinghouse inquiries to email@example.com or to
(800) 673-8311, Ext. 172.