Bi-metallic error coins are restricted to foreign countries. These coins may experience any of the many types of striking errors listed in the Error-Variety Ready Reference however, one must understand we are dealing with two components, a ring & a core. Any number of exotic possibilities or combinations of die varieties, die errors, planchet errors & striking errors can be found on bi-metallic coinage.
Misaligned Cores
A misaligned core may occur for various reasons. Three scenarios are listed below:
(1) Center hole of ring too small, grossly misshapen or both, (too
small or too misshapen to accommodate a correct fit for a
correctly-sized core).
(2) An incorrectly sized core which will not fit into a normal sized center hole of the ring.
(3) An improperly inserted core due to malfunctioning equipment
or inattentive workers, (even when both components are without flaw).
Three images below include obverse face (left), low angle view of edge (center), & reverse face of Sri Lankin 10 Rupees having a misaligned core.
2007 Slovenian two euro with grossly misaligned core.
2005 Kenyan 5 Shillings with grossly misaligned core.
Misaligned Center Hole
Either the punch or the solid ring
planchet was misaligned when the disc was peirced. The core itself
appears misaligned only because the center hole is off-set.
1996 Canadian polar bear two dollars. The center hole is clearly misaligned.
1995 Columbian 500 pesos with center hole misaligned.
Double Punched center hole
2004 Columbian 500 pesos. The center hole has clearly been double punched.
Incomplete Second Punch
1996 Canadian polar bear two dollars. While the center hole is clearly misaligned, there was an unsuccessful attempt to punch the ring a second time. Second punch scaring is evident on both obverse & reverse face (black arrows indicate second punch scaring).
Struck Outer Rings
An outer ring struck without a core will expand inward. This results in design elements that are normally restricted to the core appearing on the inner portion of the abnormally wide ring.
This type of error allows in-depth study of how the ring and core interlock and join together.
Three images below include obverse face (left), low angle view of edge (center), & reverse face of 2006 Great Britain two pound Technology coin with no core present.
1988 Italian 500 lire coin with no core present.
Struck Core
A core enters the striking chamber without having been joined or mated with its ring.
The nature of this error allows a complete study as to the method of interlock joining the ring and core together.
Obverse face (left), low angle view of edge (center), & reverse face (right) of Great Britain two pound Technology core. Note the groove along the edge of the core. The groove accommodates metal from the ring that is extruded into it. At the same time, the metal on either side of the groove is designed to penetrate the innermost portion of the outer ring when joined.
Mexican one pesos struck on core.
Struck Core from another country
A mind blower, these are an extremely rare encounter. The example shown below is from Iceland which has never used bi-metallic coinage during its entire history.
Obverse face (left), low angle view of edge (center),
& reverse face (right) of Icelandic 10 kronor.
(Center image is a comparison with a normal 10 kronor. The groove around the edge is quite obvious).
Another mind blower. While Great Britain has bi-metallic coinage, this magnetic nickel core was destined for a one euro denomination bi-metallic coin (country unknown). This core found its way into the striking chamber for a 2007 British one pound Gateshead coin.
Obverse face (left), low angle view of edge (center),
& reverse face (right) of British one pound Gateshead struck on a one euro core.
(Center image clearly indicates groove around the edge).
Wrong Ring
Occurs when a normal core is joined with a wrong ring. These errors are unequivocally rare.
Two pound 2006 Isambard Brunnel from Great Britain. The ring is is stongly attracted to a magnet. (Either elemental nickel or steel composition).
Two pound Technology from Great Britain. Ring is strongly attracted to a magnet (steel ring). The ring also has a misaligned center hole. The ring is much thinner than the core resulting in the near incomplete absence of design transfer on either face of the ring.
Two pound 2007 Gun Powder Plot from Great Britain with wrong ring. The ring also has a misaligned center hole. The ring is thinner than the core resulting in the absence of some design transfer on either face of the ring.
Ring accidentally punched from solid coin
Exotic and extremely rare encounter
An incredible occurrence; a previously
struck Hong Kong one dollar coin (solid) was center hole
punched creating a morphed outer ring. This ring was then joined with a core and struck by two pound technology dies from Great Britain.
Wrong Core inserted
An incorrect core is wrongly inserted into the ring center hole. Occurrences are quite rare.
2006 two pound technology from Great Britain having a steel core inserted before strike. (Core is strongly attracted to a magnet).
2005 Chilean 100 Pesos having an aluminum core inserted before strike.
Incomplete Trilaminar Core
Two euro denomination bi-metallic coins have a trilaminar core. The core is a disc composed of elemental nickel sandwiched by a thin layer of nordic gold on either face.
2002 two euro from Germany missing both the center nickel and outer trilaminar layer on the obverse face. Examples are known from various european countries.
Bi-metallic planchet struck with Wrong Bi-metallic Design
A bi-metallic planchet enters the striking chamber fitted with the wrong design dies.
Bi-metallic planchet struck by solid Denomination Dies
An unstruck bi-metallic planchet enters the striking chamber meant for solid planchets.
2006 Chilean 10 pesos on 100 pesos bi-metallic planchet.
2005 Chilean 50 pesos struck on a multi sided bi-metallic planchet. While Chile has bi-metallic coins, none are multi sided. Side by side comparison images of obverse & reverse faces with a normal solid, multi sided 50 pesos is shown. Only the one, five & 50 pesos coins from Chile are currently multi sided.
2005 Chilean 50 pesos struck on a multi sided bi-metallic planchet. While Chile has bi-metallic coins, none are multi sided. Only the 100 and 500 Chilean pesos coins are currently bi-metallic.
Solid Denomination planchet struck by Bi-metallic Dies
A solid planchet enters the striking chamber meant for bi-metallic planchets.
1998 British Two pound technology on unknown planchet. Struck by bi-metallic dies.
2003 Chilean 500 pesos on a bronze planchet. Struck by bi-metallic dies.
2005 Chilean 100 pesos on an aluminum planchet. Struck by bi-metallic dies.
2005 Chilean 100 pesos on a copper planchet. Struck by bi-metallic dies.
2005 Chilean 100 pesos on a bronze planchet. Struck by bi-metallic dies.
2005 Chilean 100 pesos on solid planchet. Struck by bi-metallic dies.
Definition: Bi-metallic error coins are restricted to foreign countries. These coins may experience any of the many types of striking errors listed in the Error-Variety Ready Reference however, one must understand we are dealing with two components, a ring & a core. Any number of exotic possibilities or combinations of die varieties, die errors, planchet errors & striking errors can be found on bi-metallic coinage.
A 1996 Canadian polar bear two dollars. While the center hole is clearly misaligned, there was an unsuccessful attempt to punch the ring either the first or second time. Punch scaring is evident on both obverse & reverse face (black arrows indicate punch scaring).
Definition: Bi-metallic error coins are restricted to foreign countries. These coins may experience any of the many types of striking errors listed in the Error-Variety Ready Reference however, one must understand we are dealing with two components, a ring & a core. Any number of exotic possibilities or combinations of die varieties, die errors, planchet errors & striking errors can be found on bi-metallic coinage.
Occurs when a normal core is joined with a wrong ring. These errors are unequivocally rare.
Note the following specification information regarding U.K. outer rings: 12.0 g is normal weight for a bi-metallic of this series. A two pound ring consists of the following composition and weight: Two pound ring 76% Copper, 4% Nickel, 20% Zinc Weight – 6.0 g
A two pound 2006 Isambard Brunnel from Great Britain.
The ring is is strongly attracted to a magnet. (Either elemental nickel or steel composition).
Weight: 10.30 grams.
A two pound Technology from Great Britain. Ring is strongly attracted to a magnet (steel ring). The ring also has a misaligned center hole. The ring is much thinner than the core resulting in the near incomplete absence of design transfer on either face of the ring. The ring also sheared & snapped when struck.
A two pound 2007 Gun Powder Plot from Great Britain with wrong ring. The ring also has a misaligned center hole. The ring is thinner than the core resulting in the absence of some design transfer on either face of the ring.
Article first published in 2011-02-14, Expert Advice section of Coin World
Obverse face of a 2009-S Northern Mariana Islands quarter dollar exhibits a raised crescent at its northern pole. It appears to represent a mishap during polishing of the field after the frosted texture was applied to the design.
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 tome 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 staof 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 die face.
The available evidence indicates that the step and recessed crescent were caused by a mishap in polishing the die face to a mirror-like finish. 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.
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 cweditor@coinworld.com or to (800) 673-8311, Ext. 172.
Article first published in 2011-05-09, Expert Advice section of Coin World
This Lincoln 1966 cent was struck by a horizontally misaligned obverse (hammer) die. The coin was struck in-collar and the reverse face is perfectly centered.
Image by Mike Diamond
The 20th and 21st centuries are studded with numerous spikes (and drops) in the production of specific error types. These spikes affect numerous categories of die, planchet and striking errors. Some surges in striking errors are easily explained. The year 1966 produced numerous rotated die errors (mostly 90 degrees) among Jefferson 5-cent coins. The vast majority can be traced to a single malfunctioning press. This same year brought us a less easily explained rash of Lincoln cents struck by horizontally misaligned obverse (hammer) dies. The misalignments are unusually severe, and head off in several different directions (see photo of 1966 Lincoln cent).
Lining up a quartet such errors, I was unable to match up the patterns of die scratches. Each coin was clearly struck by a different die pair; how many different presses were involved cannot be ascertained. Equally puzzling is the failure to see a similar error pattern in other denominations struck in 1966. Except for some rare instances, coinage presses are not dedicated to a specific denomination. Once the production totals for one denomination have been satisfied, the dies, collar and feeder assembly are changed to accommodate a different denomination.
Error production patterns confined to a single denomination are actually quite common and can stretch over several years. In the July 12, 2010, “Clearinghouse” column, I reported on a nine-year run of Lincoln cents with faint, oddly positioned clash marks (see photo of 1996 cent here). The clashes all occurred when the hammer die was tilted and horizontally misaligned to a remarkable degree — up to 50 percent. They’re so different from ordinary clash marks that it seems likely the mishaps occurred during installation rather than during a press run. Restricted to the years 1992 to 2000, the current count is 19 die pairs. Again, it’s unclear why the same mishap failed to occur when these presses were switched to other denominations.
An error production pattern can even be confined to a single design sub-type. In the Jan. 3 “Collectors’ Clearinghouse,” I reported on research conducted by Robert “BJ” Neff on tilted die clashes found in 1960-D Lincoln, Small Date cents (and one 1960 Small Date cent). An example of the 1960-D cent is shown here.
A tilted die clash occurs when the hammer die makes direct contact with the anvil die at an angle, leaving a set of reciprocal clash marks at one pole on each die. Such clashes are quite rare — except in this sub-type. At the time of writing, 35 such clashes have been cataloged, with at least 15 waiting in the wings for cataloging.
While examining more than 5,000 Small Date cents from both the Philadelphia and Denver Mints, Neff noticed some other intriguing patterns. Not a single conventional die clash (which produce the familiar “Lincoln in jail” effect) was found. Many of the dies from both Mints were covered by heavy die scratches, regardless of whether clash marks were visible. Die scratches are the product of intentional die abrasion, performed to remove clash marks and other types of superficial damage.
Neff also detected a high frequency of “conflicting dies” (switch-outs). These examples show clash marks on only one face; the opposite die was replaced before the press was restarted. Neff thinks that the presses responsible for the tilted die clashes and other effects were plagued by a number of problems: 1) difficulty in maintaining a horizontally oriented hammer die face, 2) difficulty in maintaining the minimum die clearance necessary to prevent a clash in the case of a planchet misfeed, and 3) an abnormally high rate of complete planchet misfeeds.
Neff thinks it’s possible that a different kind of press was used, or that a standard press was modified for the production of these Small Date cents. Whatever the changes, they didn’t work out very well and the experiment was abandoned.
Neff’s scenario only works if we surmise that the novel press design was used strictly for the small date cents. It also raises the question of why the cent design was modified after the experimental presses were abandoned. Conjecture aside, his evidence at least calls into question the standard explanation for the switch to the Large Date sub-type — a propensity for die chips to develop in digits of the small date.
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 tocweditor@coinworld.comor to (800) 673-8311,
Die adjustment strike’ remains a persistent, pertinacious myth
By Mike Diamond| May 14, 2011 10:00 a.m.
Article first published in 2011-05-23, Expert Advice section of Coin World
This weakly struck 2007 Montana quarter dollar was struck on a Schuler press, which usually doesn’t require adjustment strikes
during setup.
Images by Mike Diamond.
For, many years the writers of this column have made a conscious decision to avoid the term “die adjustment strike” when referring to an exceedingly weak (low-pressure) strike. Synonyms include “die trial,” “test strike,” “trial strike” and “setup piece.” All of these terms assume that a profoundly weak strike represents a coin that was struck as the settings of the coinage press were adjusted.
There is no doubt that die adjustment strikes have been produced through much of the Mint’s history. The word “myth” is instead directed at two common misconceptions; 1) that press adjustment is the sole or primary source of very weak strikes, and 2) that die adjustment strikes escape the Mint in numbers large enough to account for their frequent presence in the marketplace.
Weak strikes arise from two proximate causes — inadequate ram pressure and insufficient die approximation (excessive minimum die clearance). Ram pressure is the tonnage applied to a planchet of normal thickness. Die clearance refers to the closest approach the dies make to each other in the absence of a planchet.
Determining proximate cause
Determining proximate cause is often difficult; assigning ultimate cause is virtually impossible. A simple, centered weak strike could be a die adjustment strike or the product of spontaneous equipment malfunction. The latter category might encompass dies falling out of adjustment, a jam-up in the guts of the press, a mistimed or broken cam (upon which the anvil die rests), a mistimed hammer die, a slack or cracked press frame, a loose or broken knuckle joint, or a broken circuit breaker.
Numerous independent lines of evidence indicate that the vast majority of weak strikes in the marketplace are the product of spontaneous equipment malfunction, with most caused by an increase in minimum die clearance.
Absolute abundance: If weak strikes were the product of die adjustment, they should be very rare, as such test strikes are ordinarily consigned to the furnace. In truth, weak strikes are relatively common. They frequently pop up on the online auction site eBay, and the prices they command are commensurate with their ready availability. Most lower-denomination examples (cent to quarter dollar), cost $50 or less. Shown here is a recently purchased 2007 Montana quarter dollar that cost a mere $35.
Distribution by denomination: If most simple, centered weak strikes were die adjustment strikes, their relative abundance should be proportional to the total number of coins struck and dies used. Cents should therefore be the most common denomination affected by this error.
In my experience, however, the most commonly affected denomination is the dime, followed by the cent, quarter dollar and 5-cent coin. This is exactly the pattern you’d expect from weakness caused by spontaneous press malfunction resulting in insufficient die approximation. Dime planchets are quite thin, enforcing a narrow margin of error when setting the minimum die clearance. Only a slight increase in this safety margin will result in a weak strike. A slight decrease will result in a clash if a planchet is not positioned between the dies — an error that occurs on dimes with great frequency. A larger margin of error exists for thicker planchets.
This distribution pattern is also at odds with the once-popular notion that weak strikes are generated when a press is first turned on and when it’s shut off.
Occurrence with other striking errors: If weak strikes were lucky escapees from a test run, then multi-error weak strikes should be almost nonexistent. In fact, I have observed exceedingly weak strikes in association with a wide range of striking errors: off-center strike, brockaged off-center strike, double strike, triple strike, saddle strike, misaligned die error, rotated die error, clashed dies, indent, partial brockage, full brockage and struck-through. Shown here is a 1983-D Jefferson 5-cent coin with a weak second strike delivered by a rotated (30 degrees) and misaligned (35 percent) hammer die.
By Mike Diamond-Special
to Coin World |
Dec. 17, 2011 9:59 a.m.
Article
first published in 2011-12-26, Expert Advice section of Coin World
Four concentric strike lines formed on
the reverse face of this broadstruck 2000-P Jefferson 5-cent coin. The faint
concentric lines in the field are unrelated. They are concentric lathe marks —
a die error.
Images by Mike Diamond.
Multiple
strikes are often hard to spot when no movement of the coin occurs between
strikes. Collectors rely on a number of diagnostic clues to identify such
“close multi-strikes.” One such clue is the presence of concentric strike
lines.
Concentric
strike lines are circular or semicircular grooves or steps produced by the edge
of the field portion of the die and sometimes the outer edge of the rim gutter
of the die. An intermediate strike line can reflect the presence of collar
clash, which occurs when the rim gutter is damaged by contact with the top of
the collar. Close examination of spacing, contour and stepwise elevation of the
strike lines is necessary to distinguish those created by multiple strikes from
those that simply result from contact with different parts of the die
perimeter.
Strike
lines are located in the “slide zone” of off-center and broadstruck coins. The
slide zone forms as coin metal squeezes out between the dies and picks up fine
radial striations in the process. A strike line interrupts these striations.
It
would be nice if strike lines always indicated the presence of extra strikes,
but this is not the case. For example, they sometimes form opposite a “stiff
collar” error. The planchet represented by the illustrated 2000-P Jefferson
5-cent coin was not perfectly centered in the striking chamber when it was
struck. The right side rested against a stiff, but still mobile collar. The
obverse face (struck by the anvil die) was left with a sloping, featureless
shoulder that terminates laterally in a strong collar scar. On the reverse
face, four concentric strike lines can be detected between the edge of the
field and the unstruck portion of the planchet.
The
multiple strike lines were produced early in the downstroke as the hammer
(reverse) die skittered across the surface of the planchet as the collar
collapsed.
These
strike lines happen to be a minor expression of a Type I stutter strike. Had
the bounces been higher and wider, a thin crescent of die-struck design would
have been left in the gap between the inner and outer series of strike lines. A
Type I stutter strike is shown in the Dec. 28, 2009, “Collectors’
Clearinghouse” column.
I’m
not sure what caused the extensive series of strike lines present on the
obverse face of the illustrated 1993-P Washington quarter dollar. The broad
crescent on the left carries no fewer than six concentric lines. I doubt they
represent an incipient stutter strike.
On
the reverse face, strangely distant from the die-struck design, are two short but
very deep arcs of collar contact, located at 6:00 and 8:30. At this distance,
I’m skeptical that the collar could have provided sufficient resistance for
even a loose hammer die to skitter. This hypothesis would also have to
incorporate the unlikely assumption that the hammer (obverse) die contacted the
planchet in a very misaligned position and that it skittered its way to a
centered position by the time the downstroke was completed.
An
equally dubious scenario has the planchet squeezing out beneath a jittery
hammer die. Instead of a “slide zone” forming with conventional radial
striations, a series of partial rings was generated. The stumbling block here
is that this presumptive slide zone is far too wide relative to the strength of
the strike, which was quite modest. The slide zone on the reverse face is
extremely narrow.
Almost
as puzzling are the two to three concentric strike lines present on the left
side of the reverse face of a broadstruck 1998-D Roosevelt dime. The coin shows
are no signs of collar contact at all, which would seem to rule out a Type I
stutter strike. Here, at least, it seems possible that the planchet squeezed
out beneath a jittery hammer (reverse) die, leaving a series of curved lines.
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
A second case of abnormal reeding on a State quarter dollar
By Mike Diamond-Special
to Coin World|
April 07, 2012 9:58 a.m.
Article first published in 2012-04-16, Expert Advice section of Coin World
A side-by-side comparison of two 2008-P New
Mexico quarter dollars, one with normal reeding, bottom, and one with abnormal
reeding, top. The apex of each ridge on the working face of the collar was
truncated by abrasion.
Images by Mike Diamond.
A wise old aphorism from the realm of science declares that “fortune favors the prepared mind.”
Marilyn Keeney’s mind was certainly prepared when she stumbled across a second example of abnormal reeding in a State quarter dollar.
The first example — also discovered by Keeney — was reported in the Jan. 25, 2010, Collectors’ Clearinghouse. Back then she encountered a group of 2008-P New Mexico quarter dollars struck within a single damaged collar. As shown in the accompanying photo, the reeds (vertical ridges) on the edge of each affected coin are unusually low and narrow and are separated from each other by abnormally wide, flat valleys. This appearance reflects damage to the sharp tips of the corresponding ridges on the working face of the collar. The apex of each ridge was removed by abrasion or machining. Horizontal scratches in the valley floors seem to point to the use of some kind of rotating, cylindrical device.
The original discussion also included a much earlier case involving a 1964-D Washington quarter dollar. That example showed a similar, but somewhat less uniform pattern of low, narrow reeds and broad, flat valleys.
The same sort of collar damage has now been found on the edge of some 2007-P Wyoming quarter dollars. Here the damage is not nearly as severe as that seen in the earlier examples. The damage also affects only about half the edge. The edge exhibits a gradual transition from normal reeding to abnormal reeding, with the widest valleys seen at around 8:00 (obverse clock position).
At least three die pairs are represented within a group of five quarter dollars that were found by Keeney. This is not particularly surprising, as the same collar is often used through several die changes. Keeney’s two finds leave little doubt that many other cases of similar damage are yet to be discovered. In fact, I stumbled across another example while rummaging through my modest collection of coins with odd-looking reeding. This time the collar damage was detected on a 1967 quarter dollar that combines a tilted partial collar with an uncentered broadstrike. In other words, the collar was strongly tilted and a portion of it was positioned beneath the plane of the anvil (reverse) die face. The reeds are low, narrow and widely spaced (see photos).
A particularly interesting feature is seen at 2:30. Here the reeds taper strongly as they approach the top of the collar. The same phenomenon is seen on the 1964-D Washington quarter dollar. This provides a clue as to the likely cause of the damage in all these examples.
In many collars the entrance is beveled. Judging from a large sample of partial collar errors, the length of this beveled transition zone between the top of the collar and its working face is highly variable. A sloping entrance deflects the impact of a misaligned hammer die, helping to prevent damage to both the die and the working face of the collar. It also probably makes for more reliable insertion of the planchet.
In either case, the damage would be expected to occur most frequently, and achieve its greatest severity, along the upper portion of the collar’s working face. This neatly explains why the reeds sometimes taper toward the obverse face and the top of the collar.
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 tocweditor@coinworld.com or to
800-673-8311, Ext. 172.