Search Results for: MISALIGNED die

Skidding Misalignments

Part VI. Striking Errors:

Skidding Die Errors:

Skidding Misalignments

Definition: A horizontal misalignment that occurs as the hammer die is penetrating the planchet.

These two 1999-D nickels were struck in-collar by the same wildly oscillating hammer (obverse) die. In each instance the hammer die was perfectly centered when it made initial contact with the planchet. In our first specimen, the hammer die shifted to the left as it was sinking down into the planchet. This left the coin with a featureless crescent on the right side that displays scouring marks in the form of transverse (crosswise) striations. The hammer die finished its downstroke in a misaligned position. After it reached its lowest point, the hammer die shifted to the right, smearing the newly-struck design and piling the relocated metal into a series of ridges. This would be characterized as a case of slide doubling (a form of machine doubling).

In our second specimen, the hammer die shifted to the right as it was sinking down into the planchet. This left the coin with a featureless crescent on the left side that displays the characteristic transverse striations. The hammer die finished its descent in a misaligned position. After reaching the lowest point of its downstroke, the hammer die shifted to the left, smearing the newly-struck design. Every known skidding misalignment shows slide doubling in the opposite direction.

Vertical Collar Crack

Part IV. Die Errors:

Collar Cuds:

Vertical Collar Crack

Definition: Vertical collar cracks often develop at opposite poles and may presage the development of a bilateral split collar.

Vertical collar cracks are most easily seen and recognized in smooth-edged issues.

Shown below is a 1981-P nickel with vertical collar cracks at 5:00 and 11:00 (obverse clock position). It also shows peripheral die damage around the date. The latter most likely represents a die attrition error metal loss caused by a temporarily misaligned hammer die banging against the beveled entrance to the collar. The repeated impacts might have caused the collar to crack first in this area.

Vertical collar crack at the 5:00 position. Vertical collar crack at the 11:00 position.

The Mysterious 1960 Small Date Lincoln Cent

The
Mysterious 1960 Small Date Lincoln Cent

By BJ Neff, NLG

It was a pleasant surprise to have
read the 20 November, 2006 edition of Coin World and found that Eric von Klinger had written in his “Collectors’
Clearinghouse” column about my earlier work concerning the 1960 small date
Lincoln cents. Even at that time, I had felt that there was something a bit mysterious about the less than one year change to the obverse die and the Mint’s reasoning why the 1960 small date of the Lincoln cent was discontinued.

In 2006, I had established that the 1960 small date Lincoln cent master
die was the first to be made, strengthening LIBERTY and IN GOD WE TRUST from
what was on the 1959 Lincoln cent obverse master die. The discontinuation
of the small date, according to the U.S. Mint, was a problem that arose with
the working dies chipping out in the smaller 0 digit of the date. To correct
this problem, the 0 digit was enlarged along with the 6 and 9 digits for
balance in the larger date 1960 cent. On the surface, this did sound like a
plausible explanation.

We
now move forward to the year 2010 and the conception of MADdieclashes.com. This
site, which deals with the odd and unusual die clashes, was Mike
Diamond’s brain child but was built with equal contributions
from Jason Cuvelier, Bob Piazza, and myself. This is
where the second part of the story concerning the 1960 small date Lincoln cent
began.

One
of the rarer types of die clash is the tilted die clash (vertically misaligned
die clash). This is where one or both dies are tilted relative to the
horizontal plane so that when the dies do meet, only peripheral design elements
are clashed into the other die’s field near the rim. We must remember that the
working dies are convex shaped, so an appreciable tilt must be present to
produce such a die clash. Imagine the action of the hammer die hitting a
planchet with a full transfer of its design onto that planchet. Then
imagine that same die tilted to such a degree that, in the absence of a
planchet, it transfers only a small amount of its design into a small area.
With this mental picture, it’s easy to understand why the tilted die clash is
very rare.

Vertical Misaligned
Die Clash (Conventional Type) is the
definition we use on MADdieclashes.com to define a tilted die clash. If you
look at the entries for this particular die clash type, you will find that
there are over 100 assorted clashes under this heading. That doesn’t sound so
rare, does it? However, if they are all found on just one denomination for just
one year, that does make it a bit more interesting. Now add to the fact that mostly
all the tilted die clashes have been found on the 1960 and 1960D small date
Lincoln cents makes this story into a mystery. It would seem that, the 1960
small date Lincoln cent does indeed have an untold story.

      We should first look into the unusual
tilted die clashes found on the small date 1960 Lincoln cents. The first set of
clash marks (obverse and reverse) consists of the partial letters of ONE CENT
found protruding from Lincoln’s head.  Specifically, these clash
marks consist of the NE of ONE and the C of CENT.  On the reverse
die, a line from the top of Lincoln’s profile passes through the word ONE and
the C of CENT.

Working
clockwise, the second set of clash marks can be seen around the date and the
mint mark in this 1960-D cent. On the obverse face, a clash line
from the bottom of the letters in AMERICA can be seen from the bottom of the 6,
extending through the mint mark, and finally on to the lower portion of
Lincoln’s bust. On the reverse face, the mint mark can be clearly seen clashed
into the bottom of the ME of AMERICA. The jacket clash line as well as the
jacket fold can be seen cutting across the bottoms of the letters AM of
AMERICA.

The
third set of clash marks are the result of STATES being clashed into the area
below the bottom of Lincoln’s bust. On the obverse face, a partial
D from UNITED, plus partial letters from the word STATES can be seen clashed
into the area below Lincoln’s bust. The reverse face shows the lower line of
Lincoln’s bust clashed through the word STATES and into the D of UNITED. In
other specimens with a similar clash, the lower back of Lincoln can be seen
clashed into the D of UNITED and into the roof / cornice of the Memorial
building.

There are two less commonly seen die clashes that should be mentioned as
well. The first is caused by the roof of the Memorial building being clashed
onto the obverse die in the area of the date. It is seen as a rather short
bar protruding from the front of Lincoln’s jacket and at times it does extend
into the first digit of the date.

The other die clash pattern is created by the lower
back of Lincoln’s bust as it passes through either the D or E of UNITED. There
are just a few of these dies that show the partial letter D on the obverse die
and only one instance where the jacket line can be seen in bay 3 of the
Memorial building.

The other die clash pattern is created by the lower back of Lincoln’s bust as
it passes through either the D or E of UNITED. There are just a few of these
dies that show the partial letter D on the obverse die and only one instance
where the jacket line can be seen in bay 3 of the Memorial building.

It
is peculiar that having examined over 9000 small date 1960 Lincoln cents
from both mints, that only a few had the commonly seen die clash of the Lincoln cents. Mostly all
the die clashes are located well away from the center on both die faces. For those
of you who are not familiar with the common Lincoln cent die clash, please
refer to the picture below.

Now
that we have a concept of what is occurring with the die clashes, let us take
a look at a few more odd facts. Pick up any small date 1960 Lincoln cents and
the one feature that will be noted is the abundant die scratches, especially
in the areas where the clash marks can be frequently found. Presently, we
have listed 35 separate dies on MADdieclashes.com that have had clash events,
some having evidence of more than one clash event affecting that single die.
I have approximately 15 more dies to be added to the site on my desk, and I
am still searching rolls of 1960 small dates. If we look at the Memorial
Lincoln cent series, beginning with its start in the year 1959 and during any
of the next ten years, we will not find a single year with that many
different die clashes. Even in the early 1980’s, with the large amount of die
clashes found during that period that amount pales in comparison to what was
found on the 1960 small date

Another odd fact is that you can find coins struck with conflicting dies. A
conflicting die is one that will show clash marks from the opposing die,
while the opposing die is free of them. For example, a coin will have the
partial letters of STATES clashed under Lincoln’s bust on the obverse die but
does not show the corresponding clash mark of the lower bust line through the
word STATES. This can be explained by the removal of one or both dies after a
clash event, subsequent abrasion to remove the clash marks and then a failure
to put both back into service as a mated pair.

The
current practice of the U. S. Mint seems to involve replacing the obverse die
after anything more than minor clash, while abrading the reverse die. But
there is no period of time where both the obverse and reverse dies were
heavily abraded and kept in service.

The
next step is to go back and revisit the stories from the U. S. Mint
concerning the small date 1960 Lincoln cents. When the small date was first
noticed by coin collectors, the mint director, W. H. Brett, denied that any
changes had taken place. It was later that the Mint corrected that statement
and admitted that both a small date and large date 1960 Lincoln cent were in
circulation. As I had mentioned in the beginning of this article, the Mint
stated that the change was necessary to correct a problem with the small 0 in
the date chipping out. The 0 in the date was made larger, along with the 6
and 9 digit to balance the proportions of all the digits. In his 2006
column, Eric von Klinger had mentioned that I believed that
the 9 digit was actually an inverted 6 digit which was punched into the
master die. Since that time we have found that the digits in the date were
actually engraved into the master die and not applied through a punch.

After looking at the 9000+ small date cents from the year 1960, I
found none with a chipped out 0 digits — the supposed problem that ceased
its production! Yes, there were a few dies with chipped out 6 digits and more
dies with chipping in the R of LIBERTY. However, that is not the area that
the Mint had stated was the problem. So, exactly what was the malfunction
with the 1960 small date Lincoln cent?

While
we will never know exactly what did happen at the U. S. Mint  to
make it  abandon the use of the small date on the 1960 Lincoln
cent, but let us look at what we do know. The 1960 small date cent master die
was made sometime in 1959, from which was then made the various working hubs
and working dies. After the working dies were completed, the Denver mint mark
was applied to the allotted amount for service to that mint. The production
began in the beginning of the year with the Denver mint making the first of
that year’s Lincoln cent a coin press. There are two  obvious facts
that the small date Lincoln cent was odd; first, the location of the die
clash marks seen where they had never been seen before and the frequency of
the die clashes that did occur on the small date cents.

Let’s
examine the first fact. With the majority of the die clash events being the
tilted die clash variety (the reason I say majority is that I am sure one or
two will be found with a die clash marks found in the center of the die), the
hammer die may have had a different mounting system in the coin press than
seen in previous years. This tilting of the hammer die could have been a
designed feature to lessen the impact of the dies when they did clash, which
in turn would reduce the number of the obverse dies discarded after a
clash. Alternatively, it may have been just an unusual effect of
the way the hammer die was mounted in the coin press.

The
second fact points to a problem in the planchet delivery system. With the
extremely large number of clash die events occurring with the small date Lincoln
cent, it did indicate there was a problem. With each clash event, the coin
press would have to be stopped, the dies examined for damage and then either
replaced or abraded to remove the clash marks. Exactly why this problem did
occur cannot be pinpointed. However, this problem may have doomed the small
date Lincoln cent. But why make another complete set of new working dies from
scratch?

We
know that the large date and small date working hubs for 1960 were the same
physical shape. This is evident in the four working dies (3 proof dies and
one Denver mint die) that were hubbed with both a small and large working
hubs (Class III doubled dies). After the master die had completed the working
hubs and the working hubs the working dies of the small date 1960 Lincoln
cent, it may have been deemed that the master die and working hubs were too
worn to produce working dies. This would necessitate the making of a new
master die, working hubs and working dies. But why switch to the large date
version of the Lincoln cent in that same year, which duplicated the work that
had previously been accomplished on the small date Lincoln cent? Was there
some other factor that made the small date Lincoln cent uniquely different
that the previously manufactured working dies for that version of the Lincoln
cent were unusable? Again, we can only guess what that difference may have
been, but surely it was not because the digits in the date were chipping out
as the mint stated.

Another
odd phenomenon has been observed in connection with both versions of the 1960
Lincoln cent. In the making of the master die for the year, the previous
year’s master hub (or a preceding year’s master hub) was employed to make
that new master die by abrading the last two digits (in some cases the last
three digits) of the date from that master hub. The new master die was made
and the last two digits were engraved into the newly formed die.

However, it appears
that the small date 1960 master die was made from a previous year’s master
hub that had all design elements removed except for Lincoln’s bust. This is
also true for the large date 1960 Lincoln cent as well. If we compare the
word LIBERTY in a 1959 cent to the same word in both the 1960 small date
and large date cent, we can see obvious differences in the lettering.
Look at the picture to the right and while the word LIBERTY does appear to be
the same in all three examples, closer scrutiny reveals a difference in just
about all the letters.

We can also see similar differences
in the motto IN GOD WE TRUST pictured below from the two dates and the large
and small date 1960 cent.

Why did the mint
go to the extra effort of making a new master die without LIBERTY and IN GOD WE
TRUST only to have those two design elements reengraved into that new master die?
We can see that the motto had not yet migrated to the edge of the die for the
positioning of LIBERTY and IN GOD WE TRUST appear the same for 1959, 1960 small
date and 1960 large date. It has been noted by both James Wiles and me that the
1960 large date master hub was used without change up until the year of change
in 1969. In 1968, the master hub from its continuous use to make master dies
had spread Lincoln’s bust outward to a point that the motto had merged with the
rim. But that does not explain the mint’s actions in 1960 and still leaves us
wanting a better understanding of just what went on at the mint in that year.
Could this have been a situation similar to what the mint experienced with the
web note [1]?

We
now have a somewhat clearer picture of what may have happened in 1960 to the
Lincoln cent. Of course this information is all based on conjecture. Would the
Mint tell the real story? I am not too sure that they would since they did not
readily admit to the small date / large date change at the time, and then they
provided some misinformation concerning the reason for that change.

So,
the next time that you are searching those small date Lincoln cent rolls from
the Denver mint looking for RPM’s, also look for those unique die clashes. You
may be presently surprised at what you can find.

[1] The
web note was printed on a high speed printing press that did not live up to the
expectations of the Mint. The one dollar bill was the only limited note printed
on this press type.

Stutter Strike Type II

PART VI. Striking Errors:

Stutter Strikes:

Stutter Strikes due to planchet flexion (Type II):

Definition: A stutter strike is a rare error that can be thought of as the polar opposite of machine doubling. While the extra impressions of machine doubling occur after the downstroke of the hammer die reaches its lowest point, a stutter strike occurs before the downstroke has completed its downward trajectory. In a stutter strike, the hammer die makes initial light contact with the surface of the coin, but completes its descent in a slightly different position relative to the original point of contact. The result is a thin crescent of design at the outer margin of coin, distinctly separate from the definitive strike.

A stutter strike can result from movement of the die, movement of the coin, or expansion of the coin during the downstroke. It always occurs together with at least one other press malfunction or error. Associated errors include an off-center strike or broadstrike atop a stiff collar, an indent or partial brockage, or a loose die in combination with any of the aforementioned errors.

The Indian 1998 5 rupees below features a double row of denticles opposite a large indent on the reverse face. As with most Indian coins, the reverse face was struck by the hammer die. While the double row of denticles may appear to be a double-strike, closer inspection shows that it is, instead, a stutter strike.

In the case of this 5 rupees coin, the factors underlying the production of a double row of denticles appears to be the indent, in combination with a loose hammer die or die carriage. The presence of an intrusive planchet caused uneven pressure to be applied to the planchet represented by this coin. The area overlain by the intrusive planchet received the initial force of the strike, which tipped up the part of the planchet lying beyond the indent. The elevated outer portion of the planchet contacted the perimeter of the descending hammer die so that the former picked up an initial row of denticles. Simultaneous with that contact, the hammer die shifted medially and completed its downstroke, producing the second row of denticles along with the main strike. The main strike is misaligned relative to the obverse design, which was struck by the anvil die.

The stutter strike shown below is associated with an indent on the left side of the obverse face. The intrusive planchet was contacted first by the descending hammer die. This caused the right side of the underlying planchet to angle up and meet the hammer die on its way down. That light initial contact left a weakly-struck crescent on the right side of the coin that contains the TY of LIBERTY and the date. As the hammer die continued its descent, it compressed both planchets. This caused both planchets to expand in all directions. The expansion of the underlying planchet carried the lightly-struck crescent on the right side beyond the edge of the striking chamber. The hammer die then completed its descent, producing the definitive design.

The stutter strike lies lateral to the definitive design on both the obverse and reverse face. It is opposed on the reverse face by the original unstruck surface of the planchet.

Slide Doubling

PART VI. Striking Errors:

Machine Doubling:

Slide Doubling

Definition: In this form of doubling, a die drags itself through the newly-struck design, smearing the features. Strong cases of slide doubling are always restricted to the face struck by the hammer die. After reaching the lowest point of its downstroke, the hammer die shifts to one side without bouncing. As it drags itself across the newly-struck design, it piles coin metal into a series of ridges. Weak cases of slide doubling found on the reverse face have previously been assigned to “ejection doubling”, but there is no way to prove that this is actually what happened.

Forms of machine doubling combining elements of both push doubling and slide doubling do occur.

A very severe case of slide doubling is seen on this 2001-D cent. As is often the case, it is accompanied by a design ablation error. The hammer die first contacted the coin in a centered position. As it sank down into the planchet, the hammer die shifted to the northeast, erasing the newly-struck design in a crescentic area in the southwest. Having completed its downstroke in a misaligned position, the hammer die then shifted back toward the southwest, dragging itself through the newly-struck design. The design is grotesquely smeared as a result.

On the two examples (Kennedy half and Washington quarter) the green arrow indicates the direction the die traveled as contact was made (Die Ablation), with the white arrow showing the scraped planchet face. The red arrows show both the direction the die took as it returned and also shows the areas where the metal was moved and piled up. The light green arrows show details of the Slide Doubling on the Kennedy half.

Part VII. Post-Strike Mint Modifications:

Edge lettering applied after strike (incuse) (small dollar coins)

- Absent lettering (CW 4/26/10)
  - Due to bypassing the lettering device
  - Due to excessive spacing between steel wheel and lettering die
- Vertically misaligned letters (cut off at top)
- Vertically misaligned letters (cut off at bottom)
- Wrong spacing between incuse design elements
- Obliquely-oriented lettering
- Overlapping letters
- Two sets of letters
- Skipped letters
- Letters on wrong planchet
  - 2007-D Sacagawea dollar with Presidential edge lettering (CW 7/9/12)
- Chipped letter
- Lightly impressed letters (weak lettering) (CW 4/26/10)
- Unusually deep letters (coin squeezed too hard, leaving a rippled margin)
- Incomplete letters
- Smeared letters
- Edge letter font subtypes (CW 10/18/10)
- Wrong date on edge (doesn’t match any President of that year) (CW 2/22/10, 3/1/10)
  - 2009 Zachary Taylor dollar with 2010-D edge inscription (CW 2/22/10, 3/1/10)
- Edge lettering on unstruck planchet (CW 3/26/07, 3/17/08)
- Lettering die inclusion (CW 9/14/15)

Note: Edge lettering and other edge design elements may be impressed during upsetting, during the strike, by a special machine before the strike, or by a lettering device after the strike. Similar-looking defects can occur in each of these processes. Any edge design that forms a closed interlock between the edge of the coin and the collar cannot be produced during the strike since that will prevent ejection of the coin after the strike.

Special Note: Some presidential dollar coins have had the edge lettering removed outside the mint. Use caution when buying any edge lettering error.

The diagnostics for authentic presidential coin missing its edge lettering are as follows:

1. Diameter should be 26.46 mm. Coins altered outside the mint will have a diameter that is less than 26.46 mm and will have a diameter of approximately 26.21 mm.

2. The coin’s weight should be approximately 7.98 g ± .03 g. Altered coins will weigh less from the removal of the edge lettering. Weights of approximately 7.89 g are commonly seen on altered coins.

3. An unaltered presidential dollar coin will have vertical lines along the edge. These lines are created when the coin is ejected. Altered coins will not normally have these lines, but instead will have horizontal lines. These horizontal lines are from milling or similar machines used outside the mint to remove the letters and are the aftereffects of the metal being abraded off the coin.

The above image shows the vertical lines present on the edge of an unaltered presidential dollar coin with no edge lettering

Table of edge lettering errors found on the presidential and native American dollar coins

Post-strike chemical treatment

- Anti-tarnishing Experimental Rinse on Sacagawea dollars

Matte or frosted finish applied after strike

- Finish omitted on one or both faces (CW 8/1/11, 8/29/11)

Green lettering – major heading

Blue lettering – link to subject matter

Brown lettering – subject matter covered under that heading

Black lettering – no entry yet

Part V. Planchet Errors:

Alloy errors

- Improper alloy mix (CW 12/27/11, 1/30/23, 4/3/23)
  - Poorly mixed alloy
  - Incorrect proportions of metals
  - In conjunction with rolled-thick errors (1941 cents, mainly) (CW 10/15/12)
- Gas Bubbles (CW 11/19/12)
  - Intact (“occluded”)
  - Ruptured
- Slag inclusions (ES May/June 2006)
- Intrinsic metallic inclusions (ES Sept/Oct 2006; CW 12/27/10, 12/27/11, 7/21/14)
- Lamination errors
  - Loss before strike
  - Loss after strike
  - Lamination cracks
  - Retained laminations
  - Folded-over before strike (CW 10/22/12)
  - Internally split clad layer (CW 10/22/12, 6/26/17)
- Split planchets
  - Before strike (CW 8/2/10)
  - After strike
  - Wrong Denomination / Off-metal
  - Struck with another planchet on top or beneath
  - Split core (clad coins)
  - Clamshell split (CW 1/28/13)
    - Clamshell folded over before strike (CW 10/22/12, 1/23/13)
  - Hemi-split planchets (CW 10/9/23)
- Copper-and-zinc composite “shells” (ES May/June 2001)
  - Split-after-strike (N.B. these are probably all detached cap bottoms)
- Cracked planchets
- Broken planchets / coins (CW 3/14/11, 9/18/23)
  - Before strike
  - After strike
- Brittle coins (cross-classified with annealing errors)
  - Radial planchet splits (when struck out-of-collar)
  - Delayed radial stress splits (CW 5/2/22)
- Planchet cohesion errors (crumbling planchets) (CW 11/22/21)
- Ragged clips (CW 2/29/16)
- Ragged notch
- Ragged perforations (“blowholes”)
- Fissures — ragged and smooth
- Stress-induced surface irregularities (CW 4/24/17)
- Rolling-Induced Fissures

Subsurface Corrosion (CW 12/21/15)

- Plated coins
  - Copper-plated zinc cents
- Solid coins

Rolling Mill Errors

- Rolled-thick planchets
- Rolled-thin planchets (CW 8/2/10, 7/16/18)
- Tapered planchets (CW 12/20/10, 12/28/15)
  - On clad coins (clad layer absent) (CW 4/27/15)
- Rolling indentations (ES Jan/Feb 2000; CW 2/7/11)
- Rolled-in scrap (ES May/June 2006; CW 2/7/11)
  - Bristles from descaling brush (CW 3/10/03)
- Roller marks (CW 10/13/14)
- Rolled-in patterns and textures
  - Rolled-in cloth pattern (CW 3/21/16)

Blanking and Cutting Errors

- Definition
- Curved (concave) clips (CW 6/29/15)
  - Crescent curved clips
  - Bowtie clips (ES Nov/Dec 2005; CW 6/16/14)
    - Two large clips at opposite poles – ends rounded
    - Four clips — punch slices through strip with normal hole spacing
    - Struck chopped webbing
- Straight clips (CW 1/14/13)
  - Smooth straight clips
  - Irregular straight clips
  - Sawtooth clips
  - Incomplete straight clips (actually struck-in cutting burrs)
- Straight cutting burrs (CW 1/14/13, 5/16/16)
- Corner clips (“outside corner clip”) (CW 1/14/13)
- Assay clips (“inside corner clip”) (cross-classified with pre-strike damage) (CW 1/21/13, 6/12/17)
- Ragged clips (also listed under alloy errors)
- Incomplete punch (incomplete clip) (ES May/June 2005; CW 3/24/14)
- Elliptical (convex) clips (ES May/June 2005; CW 4/5/10, 7/11/11)
- Multiple clips and combination clips (CW 1/27/14)
- Blanking burrs (“rolling fold”) (ES Jan/Feb 2007; CW 1/31/11, 5/29/17, 9/4/23)
  - COIN WORLD SPECIAL: article posted HERE
- Concave blanking burrs (CW 5/16/16)
- Punched-in scrap (ES May/June 2006)

Upset Mill Errors

- Coins struck on blank (“Type I planchet”)
- Abnormally weak upset (ES July/August 2005)
- Abnormally strong upset (best seen on off-center strikes)
- “Groovy edge” (possibly from worn groove in upset mill)
- Variation in cross-sectional shape of rim/edge junction of planchet
- Struck coin sent back through upset mill
- Abnormal upset (ES Sept/Oct 2005; CW 2/27/12, 11/21/16)
  - Wide, flat edge
  - Smoothly convex edge
  - Abnormally wide proto-rim
- Squeezed-in debris (upset mill inclusion) (ES May/June 2006; CW 9/6/10)
  - Foil-like metal wraps around edge onto one or both faces
    - e.g. Copper foil on nickels (not from improper annealing)
  - Metal wire wraps around edge onto one or both faces
  - Pellet embedded in edge (CW 9/6/10, 9/22/14)

Edge design errors (impressed into planchet before strike) (includes security edge errors) (CW 6/27/16)

- Edge design missing
- Edge design present on normally plain edge (CW 6/27/16)
- Wrong edge design
- Edge design too high or too low
- Interrupted edge design
- Tilted edge design
- Broken edging die (CW 6/27/16)

Mispunched center holes (foreign only) (CW 1/7/19)

- Misaligned holes
- Double punched center holes
  - One hole centered
  - Both holes misaligned
  - Overlapping holes
  - Totally separate holes
- Irregular center holes
- Abnormally small hole
- Partial hole (from broken hole punch)
- Circular Indentation (partial penetration)
  - Due to broken-off punch tip
- Unpunched center hole
- Hole punched in planchet meant for a solid coin

Annealing Errors

- Improper annealing (due to excessive heat, prolonged exposure to intense heat, or excessive oxygen in annealing oven) (replaces “sintered plating” and “copper wash”) (ES July/Aug 2010; CW 11/30/09, 2/8/10)
  - Black, brown, red, coppery discoloration (includes “black beauty” nickels)
  - Layer of copper, often peeling

Poorly annealed or unannealed planchets (hard, brittle planchets) (CW 3/14/11)

- Broken planchets and coins (CW 3/14/11, 9/18/23)
- Radial cracks in coin (usually struck out-of-collar)

Brittle coins (cross-classified with alloy errors) (CW 3/14/11)

Abnormally hard planchets (CW 12/17/12, 8/15/22)

- 1954-S nickels
- 1983-P nickels
  - COIN WORLD SPECIAL: article posted HERE
- “Superclash” 2000-P nickel (CW 3/22/10)

On undersized or underweight planchets (CW 2/13/12)

Miscellaneous forms of mint discoloration

Plating Errors

- Incomplete plating
- Unplated cents (CW 10/26/15, 7/24/23)
- Cents struck on unplated or partly-plated foreign planchets (CW 3/10/14)
- Thin plating
- Thick plating (ES March/April 2009)
- Blistered plating
  - Circular blisters
  - Linear blisters
  - Intact blisters
  - Ruptured blisters
- Brassy plating
- Split Plating (CW 12/18/17)
  - Split Plating Doubling
- Cracked and Peeling Plating (CW 12/18/17)

Bonding/Bonding Mill Errors (ES, Sept/Oct 2002)

- Missing clad layer
  - Full
    - Before strike (CW 5/23/22)
    - After strike
    - Before rolling is completed (weight may be close to normal) (ES Sept/Oct 2002, Nov/Dec 2006; CW 5/28/12)
  - Partial
    - Before strike
    - After strike
    - Before rolling is completed
  - Thin cladding
    - With gaps
  - Missing both clad layers (struck core)
    - Core thickness (ES Sept/Oct 2003; CW 3/18/13, 2/3/20)
    - Full thickness
- Struck Clad layer
  - Separated after strike
    - COIN WORLD SPECIAL: article posted HERE
  - Separated before strike
  - Struck by itself
  - Struck on top of or beneath a normal planchet
- Clamshell separation (CW 1/28/13)
  - Clad layer folded over before strike
- Missing core
  - Partial
  - Full (Coreless or all-clad coins) (CW 12/19/11)

Irregular planchets

- Scraps/fragments (CW 12/21/09, 1/27/20)
  - Normal alloy/composition
  - Off-metal
  - Feeder finger material
  - Foil
  - Heavier than normal coin of same denomination
  - Wider than normal coin of same denomination (along at least one axis)
- Ragged clip (cross-classified with alloy errors)
- Ragged notch (cross-classified with alloy errors)
- “Blowholes” (cross-classified with alloy errors)
- Fissures (cross-classified with alloy errors)
- Cracked planchets (cross-classified with alloy errors)

Pristine Planchets (i.e. lacking tumbling marks) (CW 1/11/16)

Pre-Strike Damage (CW 11/15/10, 11/15/10, 1/23/12, 1/30/12, 12/15/14, 4/13/15, 6/8/20)

- COIN WORLD SPECIALS: articles posted HERE and HERE
- Assay clips (cross-classified with blanking errors)
- Rim burrs (CW 1/31/11)
- Accidentally and intentionally “re-sized” planchets (CW 9/15/10)
- “Crimp marks” (mostly found on off-metal errors, e.g., 5c/1c, 5c/10c)
- Rockwell test mark in planchet (circular or oval dimple) (ES July/Aug 2006; CW 10/15/18)
- Planchet with adjustment marks (gold and silver planchets filed to return heavy planchets to normal weight)
- Edge rolled, squeezed, and folded-over (or with thin apron produced) (CW 11/15/10, 1/23/12, 6/15/20)
- Pre-plating damage (zinc cents) (CW 1/23/12)
- Post-plating damage (zinc cents) (CW 11/15/10)
- Scraped-in debris (CW 2/23/15)
- Repetitive pre-strike damage (CW 12/15/14)
- Other forms of pre-strike damage
  - Gouged (CW 1/14/19)
  - Crushed (CW 4/13/15)
  - Scraped (CW 2/23/15)
  - Torn
  - Crumpled (CW 8/15/11)

Inter-strike Damage (CW 1/9/12, 8/20/12)

- Cancelled or defaced between strikes (CW 3/25/13)

Trans-strike damage (CW 7/12/21)

Wrong planchet and off-metal errors

- Wrong planchet, correct composition
- Off-metal
  - Domestic planchet (CW 6/22/20)
    - Monroe dollar coin struck on a clad dime planchet
    - 1987-P Jefferson nickel struck on clad stock
  - Domestic struck on foreign planchet
    - 1941-P Lincoln cent struck on a Panama 1¼ bronze centesimos
    - 1920-P Lincoln cent struck on a Argentina 10 centavos planchet
    - 1905-P Barber dime struck on a Panama or Philippines five centavos planchet
    - 2000-P Sacagawea struck on a Ghana 100 Cedis ring
  - Foreign planchet
  - Unidentified origin and purpose (orphan) (ES Sept/Oct 2006, Nov/Dec 2006, March/April 2011, May/June 2011; CW 5/10/10, 12/19/11, 1/30/17, 11/30/20, 4/4/22)
  - Defective and damaged off-metal planchets (CW 3/21/16)
  - Foreign denomination struck on U.S. planchet
    - 1970 Philippines 25 Sentimos on a U. S. cent planchet (3.1 g)
    - 1972 Philippines 1 Peso on a U.S. clad 50 cent planchet
    - 2000 Canadian Pride 25 cent coin struck on a United States nickel planchet
  - Pure copper quarters and dimes (covered under bonding mill errors)
  - Pure clad dime (covered under bonding mill errors)
- Wrong stock errors
  - Correct composition
  - Off-metal (e.g, 1987-P nickel struck on clad quarter stock) (CW 4/22/13, 9/23/13, 9/10/18)
  - Transitional stock planchets (CW 9/23/13)
- Business strike on special off-metal planchet (CW 2/10/20)
  - (e.g., 40% silver-clad 1974-D and 1977-D Eisenhower dollars)
- Special strike on business planchet (CW 2/10/20)
  - (e.g., 1973-S Eisenhower dollar on Cu-Ni clad planchet)
- Business strikes on proof planchets (CW 11/14/11)
- Proof strike on business planchet
  - COIN WORLD SPECIAL: article posted HERE
- Wrong date error (covered under mules and die manufacturing errors)
- Double denomination errors (CW 10/3/22)
  - Same year
  - Different year
  - Over pre-existing wrong planchet/off-metal error (ES Sept/Oct 2017; CW 2/10/2014)
- Dual country (CW 3/21/11)
  - Same year
  - Different year
- Intentional overstrikes (not an error)
- Transitional planchet errors (“wrong series”) (ES Sept/Oct 2001; CW 3/28/16, 8/22/16)
  - Composition/year mismatch with non-overlapping production schedule
    - 1943 bronze cents (CW 4/11/16)
  - Composition/year mismatch with overlapping production schedule
    - 1965 silver dimes and quarters
    - 1964 clad dimes and quarters
  - Intra-year design/composition mismatch
    - 1991 Russia 10 kopek (ES Sept/Oct 2001)
  - Forward-jumping transitional planchet errors (CW 3/20/17)
  - Transitional/wrong denomination error
    - (e.g. 1965 quarter struck on silver dime planchet)
  - “Long pause” transitional planchet errors (CW 4/5/21)
- Struck on smaller planchet or coin
- Struck on same size planchet or coin
- Struck on re-sized planchet (dime design struck on cut-down cent planchet)
- Struck on larger planchet or coin (CW 8/22/22)
  - 1981 cent on nickel planchet, uniface reverse
  - 1981 dime on cent cap
  - 1981 cent design struck on Susan B. Anthony dollar (several known)
  - 2006 Chilean 10 pesos struck on a 100 pesos bi-metallic planchet
  - Canadian “assisted errors” 1977 – 1981
  - Malaysian “assisted errors” 2005-2007
- Struck on loose clad layer (covered under bonding mill errors)
- Weld seam planchets (controversial) (CW 9/24/12)
- Coins struck on washers, gears, and other hardware
- Coins struck on “aluminum” feeder fingers
- Experimental issues (CW 11/23/15, 5/23/16)
  - Experimental wartime planchets (CW 12/7/09, 12/21/09)
  - 1999 and 2000 state quarters on experimental planchets – tests for Sacagawea dollar (CW 11/26/01)
  - 1999 Susan B. Anthony dollars struck on experimental planchets (CW 8/5/02)
  - 1974 aluminum and bronze-clad steel cents (CW 1/13/03)

Bi-metallic errors (foreign only) (ES Nov/Dec 2005)

- Misaligned core (ES May/June 2007; CW 3/6/23)
- Misaligned center hole (ES Sept/Oct 2007)
  - Well-seated core (CW 3/6/23)
  - With misaligned core (CW 3/6/23)
- Double-punched center hole
- Unpunched center hole
  - Solid disc of ring metal (CW 3/26/18)
  - Solid disc of ring metal with embedded core
  - Solid disc of ring metal with core indent
- Ring with incomplete punch (ES Sep/Oct 2007)
- Core with incomplete punch
- Struck outer ring (ES Jan/Feb 2007)
- Struck core (ES Nov/Dec 2006)
  - From another denomination
  - From another country (ES Sep/Oct 2009, Nov/Dec 2011)
  - Struck by solid-denomination dies
- Wrong core inserted (ES Sep/Oct 2013; CW 10/17/22)
  - Core-sized scrap disc of ring material inserted into disc
- Wrong ring (ES March/April 2007; CW 10/10/22)
- Ring accidentally punched from solid planchet
- Ring accidentally punched from solid coin (ES Nov/Dec 2008)
- Struck ring from another country (restruck)
- Struck core from another country (restruck)
- Unstruck core inserted into struck ring and then restruck
- Abnormally small core (controversial)
- Abnormally wide center hole (controversial)
- Abnormally thin core
- Abnormally thick core
- Abnormally thin ring
- Abnormally thick ring
- Incomplete trilaminar core
  - Missing one layer (ES Mar/Apr 2010)
  - Missing two layers
- Core punched out of ring strip
- Ring punched out of core strip
- Bi-metallic planchet struck by solid-denomination dies
- Solid-denomination planchet struck by bi-metallic dies (ES Mar/Apr 2014)
- Bi-metallic planchet struck by wrong bi-metallic design

Green lettering – major heading

Blue lettering – linked to subject matter

Brown lettering – subject matter covered under that heading

Black lettering – no entry yet

Error-ref.com News

The Latest News about the Error-Variety Ready Reference

July 9th, 2012 – Welcome to this unique site. Through the efforts of our staff, we hope to bring to you, the collector, the best and most pertinent information available concerning error and variety coins. While the site is not yet complete, our plan is to continuously work on gathering information that is of interest to the E/V community.

This page will show you our progress by linking to new entries. So, stop by often and see what is new.

– BJ Neff

We have added a new page to the site; “Compound and Complex Errors”. This page will deal with the more unusual errors that have occurred. Make sure to check out this new entry!

– Author Unknown

July 16th, 2014 – Error-ref.com has found a new home and a new look. The site has been officially transferred over and you may encounter some errors. If you will please notify us of these errors.

Thank you.

– BJ Neff

June, 2017 – We added “Stress-Induced Surface Irregularities” to our list of errors and varieties.

May, 2017 – We added or updated “Vickers Test Mark Left In Die”, “Floating Collar Clash”, and “Field-Restricted Struck-Through Errors” to our list of errors and varieties.

– JC Stevens

February 20th, 2017 – We just added “Defective Punch” and “Detail-Erasing Die Wear” to our list of errors and varieties.

August 19th, 2016 – We added “The Henning Nickel” to Part XI. Non Errors.

– Author JC Stevens

October, 2021 – We added “Crenellated Rim,” “Feeder/Ejector Scrapes,” “Inverted Hump,” “Partial Collar,” and “[Struck Through] String.” We updated “Rockwell Test Mark In Planchet,” “Pivoted Die Error,” “Collar Damage,” and “Chatter Clash.”

November, 2021 – We added “External Disc Impressions.”

December, 2021 – We added “Hidden Initials And Symbols” and “Illicitly Applied Die Impressions.” We updated “Ejection Impact Doubling,” “Rim-restricted Design Duplication,” and “Die Rings (Tiny Rings, Semicircles, Crescents, And Spirals).”

January, 2022 – We updated “Die Scrapes.”

January, 2023 – We added “Design/Composition Mismatches” and “Die Exfoliation Errors.” We updated “Radial Flow Lines” and “[Saddle (Tandem) Strikes] On Quarter Dollars.”

February, 2023 – We added “Deformed Collar” and “Edge Strikes.”

April, 2023 – JC Stevens updated “Henning Nickel.”

May, 2023 – We added “Misaligned Hubbing (Uncorrected),” “‘Spackled’ Dies (Intentionally Applied Grease),” “Multiple Misaligned Strikes,” “Grease-Generated Counterbrockage,” “Exogenous Floating Die Clash,” and “Ejection Doubling.”

July, 2023 – We updated “Wrong Ring.”

October, 2023 – We added “Yanked-Out Fillings” and “Encircling Pressure Bumps.”

December, 2023 – We added “Struck-In Die Fragments,” “Misaligned Collar Clash,” “Catastrophic Collar Failure,” “Anvil Die Collar Clash,” and “Earliest Inverted Die Setup.”

March, 2025 – We updated “Rim-Restricted Design Duplication.”

– Shane Daniel

Collar Clash

Part IV. Die Errors:

Die Clash:

Collar Clash

A collar clash represents damage to the rim gutter of the die from contact with the collar. It shows up most clearly in reeded issues, where it takes the form of serrations along the top or the edge of the design rim. In an off-center strike, a collar clash will appear in the form of parallel grooves in the “slide zone”.

Collar clash is far more common on the hammer die. It occurs when a temporarily misaligned hammer die collides with the top of the collar and/or scrapes along its working face.

When collar clash occurs on the anvil die, it is probably from a repeated up-and-down scraping action of the die neck against the working face of the collar. However, a sharp sideways impact that drives the die neck into the collar’s
working face could also produce this pattern of serrations.

Below is a 1997-P dime with a collar clash from from K8-K12.

Another collar clash on a 1980-P Kennedy half dollar seen from K7-K11.

Below is two views of a defaced state quarter working hub with evidence of a previous collar clash. The grooves match the width and spacing of the reeding found on a quarter. The face was ground off down to the level of the rim gutter leaving some of the collar clash marks visible.

Chatter Clash

PART IV. Die Errors:

Clashed Dies:

Multiple Clash Marks:

Chatter clash

Definition: A closely-spaced group of clash marks reflecting an uninterrupted series of die clashes, with slight die movement of the hammer die between each impact. Most cases of chatter clash reflect a sideways movement of the hammer die. Very rarely does one encounter a case of rotational chatter clash.

This 1998 cent was struck by a hammer die that was horizontally misaligned toward the northwest. The die shift was incremental, with a clash occurring after each change in position. The result is at least 5 sets of clash marks moving in the southeast direction on the obverse face.

This double-struck 1994 Indian 2 rupee coin features several sets of rotational clash marks on the reverse face. The absence of clash marks on the obverse face suggests that this die was switched out before the strike that generated this coin. Since the obverse die functioned as the hammer die in this press, and since most die rotations affect the hammer die, it stands to reason that it was the hammer die that underwent an incremental rotation during the series of clashes reflected on the reverse face.