When Clair Alan Hardesty received his 2009-S Proof set, he
immediately saw that something was wrong with his Northern Mariana
Islands quarter dollar.
A thin, bright line could be seen arcing across the obverse face,
cutting through the legend united states of america. The end-points of
the line coincided with the inner margin of the design rim and
extended from a point above the t of united to the e of america.
Recognizing it as a probable die error, Hardesty sent the coin to
PCGS under their Mint error service. The response was disappointing
and confusing. A customer service representative informed Hardesty
that the grader had determined that “this is not an error coin. They
are as struck.” Hardesty insisted that they look again, and the second
response was similar, “The coin was re-evaluated for the error a
second time. The information you provided was taken into account.
Unfortunately the graders did not feel it was an error.”
Undeterred by the failure of PCGS to recognize a grossly obvious
flaw, Hardesty sent the coin to me for analysis. Upon receiving the
coin I immediately agreed that this is a significant die error. We
next had to determine what kind of die error we were dealing with.
The bright arc is actually a sharply defined step. The crescentic
area demarcated by the step is raised above the rest of the field.
This indicates that the corresponding field portion of the die was
recessed. The field has a mirror-like Proof finish above and below the
step. However, faint radial ripples distort the surface of the
abnormally polished crescent.
How was recess formed?
The question now turned to how this recess formed. A die dent
seemed unlikely as this would have probably dulled the finish.
A major clue as to what transpired can be found in the letters
that cross the step. Above the step the letters are narrowed or
constricted. This is most evident in the letters sta of states and the
word of. Thinning of design elements is caused by only one thing —
mechanical removal of the field surrounding each design element. As
the field is lowered on the die face, the letters get narrower. This
is because the sides of each letter converge as you go deeper into the
The available evidence indicates that the step and recessed
crescent were caused by a mishap in polishing the die face to a
Die polishing is the exclusive province of Proof dies and dies
that strike collector issues, like the coins in the Special Mint sets
issued from 1965 to 1967. The intent is to create a highly reflective
surface on the die and on the coins it strikes. If taken too far, this
process can cause thinning of design elements and loss of details in
the lowest parts of the design.
Die polishing of this sort should not be confused with intentional
die abrasion designed to remove clash marks and other forms of die
damage. Primarily applied to circulation-strike dies, such salvage
attempts typically leave lots of die scratches and certainly don’t
produce a mirror-like finish. The term “die polishing” is still
sometimes used to refer to such salvage efforts, causing interminable
confusion among collectors.
Alternative scenario unlikely
Hardesty proposed a slightly more complex scenario to explain this
unusual error. He suggests that a strongly misaligned obverse (hammer)
die collided with the top of the collar and that this collision left
the step and the recess. He then suggests that Mint workers tried to
salvage the die by polishing the damaged area.
A scenario involving collar clash and a subsequent repair job
seems unlikely to me. It makes no sense to a repair such a heavily
damaged die. There are no recorded cases of collar clash this offset
and this severe among circulation strikes. A die dent generated by
such a collar clash is unlikely to produce such a sharp step. Finally,
the outer margin of the obverse die face retained its convexity
(leaving a bowl-shaped perimeter on the coin). A collision as severe
as Hardesty proposes should have flattened out that convexity.
Since die errors are repetitive, it is possible that more of these
2009-S Northern Mariana Islands quarter dollars remain to be found.
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