PART IV. Die Errors:

Vertically Misaligned Die Error (Tilted Die Error)

Definition:  A die or the entire die assembly can fall out of adjustment so that the two opposing die faces are no longer parallel.  The tilted die will strike the planchet at an angle.  One pole will be very well struck while the opposite pole will show little or no design.  The pole that is well struck will show a very strong design rim and often finning of the rim.  The opposite pole will retain the original proto-rim of the unstruck planchet.  Extreme tilted die errors usually show a horizontal misalignment as well.  That’s because when a die tilts down, it also tilts in.

This 1972-D half dollar shows a combination die alignment error.  The vertical misalignment co-occurs with a 90 degree rotated die error.

 

PART IV. Die Errors:

Die Clashes:

Radically Misaligned Die Clashes

Definition: A radically misaligned die clash is one that is produced by a hammer die with a huge horizontal misalignment and also a vertical misalignment (tilted die).  Only the downward-tilted pole of the hammer die contacts the anvil die.  Design transfer can occur on either die or both dies.  The mark left on the hammer die by the anvil die generally consists of a curved impression of the edge of the field portion of the die and some adjacent letters.  The clash marks are invariably light.

These peculiar clash marksare unlikely to be caused by a press malfunction during a press run.  It is believed that the dies contact each other during installation, perhaps as one die is dropped on the other.

PART IV. Die Errors:

Die Clash:

Vertical Misaligned Die Clash (Conventional)

Definition: Vertically misaligned die clashes of the conventional sort are much rare than horizontal misaligned die clashes.  The simple reason is that vertical misalignments are much rarer than horizontal misalignments.

During a vertical MAD clash, one pole of a tilted die is driven into the corresponding pole of the opposite die. Whatever peripheral design elements occupy this pole is picked up by the opposite die.

Part IV. Die Errors:

Collar Clash:

Misaligned collar clash

Definition: Collar clash located medial to the coin’s design rim.

A misaligned collar clash requires several pre-conditions:

1. A horizontal misalignment of the hammer die great enough to extend past the collar’s entrance.
2. Alternatively, you’d need a horizontal misalignment of the anvil die and collar severe enough to bring the edge of the collar’s entrance beneath the hammer die.
3. Lack of a beveled entrance, so that the ridged working face of the collar meets the top of the collar without any transition zone.
4. A collar that resists depression when struck by the hammer die (i.e., a stiff collar error).
5. A striking chamber that is either empty or occupied by a planchet that lies below the top of the collar.

As with any collar clash, the only hope of confidently identifying a misaligned collar clash lies among reeded issues. The ridged working face of the collar will leave a set of serrations that encroach onto the field portion of the die. On the coin, the characteristic serrations will be found in the field, rather than on, or at the edge of, the design rim.

This 1995-P dime displays a misaligned collar clash on its left side. The serrations produced by the clash extend from the internal margin of the design rim to the outermost portion of the field.

Part II. Die Varieties:

Misaligned hubbing (uncorrected)

Definition: A working die that receives an uncorrected misaligned impression
from a working hub.

Misaligned hubbings occur every so often. If the initial hubbing is misaligned, it is always corrected by a properly centered hubbing. Sometimes the offset hubbing occurs after the properly centered hubbing. In either case, the result is a Class IV doubled die (offset hub doubling).

Uncorrected misaligned hubbings are currently unknown among domestic or world coins. However, Daniel Carr has created some silver rounds that replicate the appearance of an uncorrected misaligned hubbing.

This American Silver Eagle bullion coin was overstruck by a pair of private-issue dies that closely replicate the design of the Walking Liberty half dollar. The host coin’s design has been nearly obliterated. The obverse design was engraved directly into the obverse die in a 15% offset position.

While the result looks like a misaligned die error, there are key differences:

Part VI. Striking Errors:

Die alignment errors:

Horizontal misalignment:

Multiple misaligned strikes

Definition: The presence of two or more misaligned strikes on the same face of the same coin. The position of the affected die can be stable or quite unstable.

It is rare for a coin to be struck more than once by a misaligned die. It is even rarer for those strikes to be well-separated as the result of die instability. This undated India 10 rupees coin (2019 – present) features a 31% off-center first strike and a series of at least six additional off-center strikes that were all 79% off-center. The hammer die was properly centered during the first strike. However, during the later off-center strikes, the hammer (obverse) die became progressively more misaligned until it finally migrated beyond the coin. The coin showed very little movement during those later strikes and the anvil die remained fixed in position.

Part IV. Die Errors:

Die exfoliation errors

Definition: A thin layer of steel spalls off the die face, rendering the design slightly indistinct and leaving the surface with a grainy microscopic surface texture.

The single purported example of a die exfoliation error appears on a 1983-P nickel struck by a slightly misaligned obverse die and a cracked reverse die. The left side of the obverse face features an unusual 50% cud with an indented surface. The right side of the obverse face displays a uniformly grainy surface texture and an indistinct design. This texture is not one found in association with capped die strikes or any known struck-through error. Also unlike a capped die strike, the design shows no ripples surrounding the design or tendrils extending from the design. The indentations within the cud show a smooth texture, indicating that whatever caused the grainy texture was confined to the area to the right of the cud.

The relief of the design is unexpectedly low, relative to the amount of detail present. Also, many of the letters and numbers are oddly attenuated. These features are also inconsistent with any known struck-through error.

Since alternative hypotheses are deficient in explaining this error, it would appear that a very thin layer of die steel separated from the die face.

Part IX. Post-Strike Mint Damage:

Illicitly applied die impressions

Definition: Planchets and coins that have a new design impressed into them inside the Mint but without the use of a coining press. These illicit impressions have one or more of the following characteristics.

1) Frequent use of proof dies, normal and impaired.

2) Frequent use of proof planchets, normal and impaired.

3) Presence of odd patterns and textures.

4) One or both designs strongly misaligned (horizontally, vertically, or rotationally).

5) Design impressions often weak.

6) Multiple, overlapping impressions common.

7) Nonsense die sometimes used on one face.

8) Counterfeit die sometimes used on one face or superimposed over the original illicit die impression.

9) Oversized coins and planchets sometimes used to host the illicit impression.

10) Wrong planchet or different denomination sometimes used to host the illicit impression.

11) Heavy damage to the planchet or coin prior to, coincident with, or following upon, the illicit die impression.

12) Dies often heavily damaged or vandalized.

13) Opposing designs applied sequentially, rather than simultaneously.

14) Creation of false brockages before, during, or after application of the genuine die.

15) Raised image confined to one face.

16) Strange forms of doubling, often of an extreme nature.

This nickel planchet received two sequential impressions from either the same obverse die or two different 5-cent obverse dies. Both designs are weakly impressed and off-center toward the left. One face is rotated 90 degrees relative to the other.  Both dies were also tilted. One obverse design shows strong doubling while the other is grossly smeared. During each impression, the opposite face rested against a textured surface. One or both designs seem to have been damaged after the final impression was generated.

Depending on their provenance, how convincing they look, how much damage is present, and whether proof dies and planchets were involved, these creations can fetch prices ranging from a few tens of dollars to over $10,000.

The status of such coins as “errors” is highly controversial. Though created inside the Mint by personnel employing genuine dies, the use of techniques other than a coining press make them more like fantasy pieces.

Part VI. Striking Errors:

Skidding Die Errors

Definition: Skidding die errors occur when a laterally-shifting die slides across the surface of a planchet or coin, scraping the surface.  Severe cases always involve the hammer die.  The error can occur as the hammer die is completing its downstroke, after the hammer die has reached the lowest point of its downstroke, and during the first moments of retraction.  These errors can occur in the course of a single strike or during a second strike.  Different names are applied to skidding die errors depending on their appearance and when they occur.  Four types of skidding die errors are recognized and are the subject of separate entries:

1. Skidding misalignment.  This occurs as the die is penetrating the planchet.
2. Design ablation error.  This occurs during a second strike as a horizontally shifting hammer die scrapes off the design generated during the first strike.
3. Design decapitation error.  This occurs during the retraction phase as a horizontally shifting hammer die removes the highest points of the design.
4. Slide doubling.  This occurs immediately after the hammer die reaches the lowest point of its downstroke.  The die shifts laterally without lifting up, smearing the design and piling up the relocated metal into a series of ridges.  This entry can be found as a sub-entry of Machine Doubling.

 

This 1999-D nickel shows a skidding misalignment on its obverse face.  At first contact the hammer die was in its normal, centered position.  As it sank down into the planchet it shifted to the left and finished its downstroke in a misaligned position.  After reaching the lowest point of its downstroke, the hammer die shifted to the right, smearing the newly-struck design.  This second movement falls into the category of strike doubling.

Reduction lathe doubling (master hub doubling)

Master die doubling (master die with a doubled die variety) (CW 7/27/20)

Broken hub (chipped hub) (CW 12/23/13, 5/21/18)

Hubbed-in debris (CW 5/27/13, 1/17/22)

Broken punch

Damaged punch

Defective punch

Longacre doubling (probably impressions of punch shoulders)

Doubled dies (incl. tripled dies, etc)

• • Rotated hub doubling (Class I) (CW 8/8/16)
    • 1872 Seated Liberty dime with 175 degree rotation (ES July/August 2003; CW 2/10/03)
  • Distorted hub doubling (Class II)
  • Design hub doubling (Class III)
  • Offset hub doubling (Class IV)
  • Pivoted hub doubling (Class V)
  • Distended hub doubling (Class VI)
  • Modified hub doubling (Class VII)
  • Tilted hub doubling (Class VIII)
  • Single-squeeze doubled dies (often attributed to Class VIII) (CW 2/14/05, 9/12/05)
    • Centrally-located doubling (CW 3/21/22)
    • Peripheral Doubling (CW 8/8/04)
  • Weaker impression hubbed last (e.g., 1963-D cent) (CW 6/14/10)
  • Centrally-located doubled dies (CW 4/15/19)
    • Rotated

Weak or incomplete hubbing (always part of a doubled die)

Tilted hubbing (always part of a doubled die)

Misaligned hubbing (uncorrected) (CW 5/30/22)

Repunched date (ES July/August 2012; CW 12/14/09)

• • 1956-D cent with repunched 5 (controversial) (CW 9/20/04, 7/16/12)
  • 1957-D cent with repunched 7 (controversial)

Re-engraved date (on master die or working die)

Blundered date (on master die or working die)

• • 1853 Half Dime with Inverted Date, Repunched with Corrected Date

Misplaced date (e.g. digits in denticles) (CW 4/21/03)

Misplaced mintmark

Phantom mintmark (working hub has mintmark incompletely removed)

• • (e.g. faint D and S mintmarks in cents from the late 1990s)

Dual mintmarks

• • 1980 D & S cent (recently delisted)
  • 1956 D & S cent (controversial)

Horizontal mintmarks (inevitably repunched)

Tilted mintmarks (punched in at an angle) (CW 7/28/14)

Rotated Mintmarks (CW 7/28/14)

Inverted mintmarks

Deeply-punched (high-standing) mintmarks (CW 9/29/14)

• • High-standing D mintmark (1987-D, 1988-D, and 1989-D cents)

Weakly-punched mintmarks

Repunched mintmarks (CW 1/20/20)

• • Overlapping mintmarks
  • Totally separated mintmarks
  • Two different fonts
  • Large over small mintmarks

Repunched mint marks on the Jefferson nickel; Book by James Wiles (downloadable version)

Overmintmarks

• • 1938-D/S Buffalo Nickel
  • 1944-D/S cent

Other repunched or re-engraved design elements

• • Denomination
  • Letters
  • Assay value
  • Other design elements

Omitted mintmarks

• • 1982 “no-P” Roosevelt dime
  • 1990 Lincoln proof cent without S-mintmark

COIN WORLD SPECIAL: article posted HERE on 1975-S Roosevelt dime without mintmark.

Omitted date (foreign only) (CW 4/28/14)

Other omitted design elements

Large over small mintmarks

Different mintmark styles and sizes

Overdates (CW 1/23/17)

• • Caused by repunching or re-engraving
    • 1892 over an 18(8)2 Peruvian 1/2 Dino
    • 1958-D Lincoln cent with repunched 7 digit (debunked)
  • Caused by second hubbing of different date (Class III doubled die)
  • Caused by grinding off earlier design and rehubbing or repunching (CW 1/23/17)
    • 1943 over 1942 Jefferson nickel

Dual Dates (earlier date faint)

• • Caused by erasing earlier date on working hub
  • Caused by removing earlier date from working die and re-hubbing (e.g. 1975 Bahamas 5c with faint date “1973” on opposite face)

Wrong dates

• • Date later than final date of issue (e.g., 1913 Liberty Head nickel)
  • Date earlier than first date of issue (e.g., 1954 Mexico 5 centavos – small size)
  • Wrong digits (e.g., 1393/1893 Peruvian peso)
  • Transposed digits

Blundered dies (various types) (CW 8/18/08)

• • Misspelling on working dies
  • 1801 Large Cent: United misspelled IINITED
  • 1863 Patriotic Token; SPOT misspelled (SPOOT)

Special Finish Errors (Proofs, Mint sets, Special Mint Sets, Satin Finish, etc.)

• • Frosting slop-over (proofs) 
  • Offset frosting (proofs) (CW 2/21/11)
  • Design removed by proof polishing (CW 2/21/11)
  • Field lowered by proof polishing (CW 2/14/11)
  • Frosting applied in wrong place (CW 2/28/11)
    • COIN WORLD SPECIAL: article posted HERE “Frosted Freedom” $50 and $100 platinum coins (CW 8/1/11)
  • Frosting omitted
  • Stencil outlines (CW 2/18/13)
  • Incomplete Proof Laser Frosting (CW 9/12/16, 9/6/21)

Design Extension Dimples (CW 4/18/11)

• • COIN WORLD SPECIAL: article posted HERE

Edge Lettering Font Variants

• • Presidential dollars (4-5 types) (CW 10/18/10)

Hidden Initials And Symbols

• • Applied to working die or master die
    • 1973 and 1974 Mexico Bronze 20 Centavos
    • 1984 Mexico 1 Peso
  • Applied to working hub
    • 2023 “extra V” cent (CW 3/27/23)

Green lettering – major heading

Blue lettering – linked to subject matter

Brown lettering – subject matter covered under that heading

Black lettering – no entry yet