Plating Split-Doubling (Split-Line Doubling)

Plating Split-Doubling (AKA Split-Line Doubling):

At this point there is no official phrase for this phenomenon; web searches lead Plating Split-Doubling to Ken Potter and Split-Line Doubling to Mike Diamond, but it is unclear who coined either term. The characteristics are: a split in the copper, revealing a light blue to greenish area (which is exposed zinc), that shadows a device and makes it appear doubled.

Plating Split-Doubling is notoriously misidentified as RPMs, Doubled Dies and on Broadstrikes as having been Double Struck (when it has not).

The phenomenon is commonly located on either the obverse or reverse of copper plated Lincoln cents. Plating Split-Doubling is also boldly found on some Broadstrikes and Off-centered Lincoln cents. While it can be found almost anywhere, it specifically tends to inhabit the regions nearest the rim and is associated with the design elements. The devices most frequently identified on a normal strike are the mintmark (MM), USoA, INGWT and sometimes parts of the memorial. The split itself can be very thin and hug a device or some distance from a device and wide to the point that it appears almost comical on some Broadstruck Lincolns.

While it would seem possible that the split is a tear that is facilitated by the raised struck parts of the coin holding the copper in place as it travels too quickly and too far – it appears more likely the sharp edge of the incuse die devices weaken and help to instigate the copper to split open and reveal the zinc as the copper it is stretched too thin. Why it happens inconsistently appears unknown.

Below are two examples: the obverse of a 1993 Off-center Lincoln and the reverse of a dateless Broadstruck Lincoln, both exhibit Plating Split-Doubling. The Off-center has the appearance of an extra profile while the Broadstruck has various parts of the memorial splitting open. Points 1, 2 & 3 (on the illustration below) appear to originate from the same location at the first moment of impact next to the portrait of Lincoln, and then they appear to travel apart as the copper is over stretched.

Below is a 1992D and a 1989D both with commonly seen Plating Split-Doubling on the MM and the devices on the reverse, notably USoA and the memorial. The black arrows in the first photo show the splits while the white arrows show mild Machine Doubling that has also occurred.

Here is the approximate distance for specific devices from the rim on Lincoln cents:<
LIBERTY: .5mm
IGWT: .3
MM: 1-1.5mm
Bottom of bust: .6mm (not sharp)
USoA: .2mm
ONE CENT: .2-.4mm

Most splits are occur on LIB, the upper parts of IGWT, USoA, the lower parts of ONE CENT, the date, the outer parts of the memorial and, while not as close to the edge yet yielding many examples, the lower and inner loops of the D MM.

__________________

Jason Cuvelier

The Non-Hub-Doubling Resource Page

I decided to collect here, in one place for your reference, all of the different forms of doubling that you may come across while searching Lincolns.  There are many pitfalls on the path to recognizing the classes of doubled dies, so I endeavor here to show a comprehensive list, with illustrations, of all of the forms of doubling which are not the result of hub doubling. Again, what follows are not doubled dies, though are often confused as such.

Section 1: The basics – the following are the most common causes of doubling and do not generally carry any premium.

Machine Doubling (Also Machine Damage Doubling, or Strike Doubling): This occurs when a loose die bounces (push-type machine doubling) after the initial strike and hits the planchet again in a slightly offset position, flattening a portion of an already struck device, creating a “shelf-like” doubling effect that cuts into the normal size of the device. This is often misconstrued as a doubled die by novices, but is common and essentially worthless. Sometimes the die will “slide” rather than bounce, creating a smeared look to the devices. (slide-type machine doubling). Ejection doubling is another form of machine doubling where the coin “sticks” to the anvil die when being ejected from the striking chamber. In addition to the examples below, please see Jason Cuvelier’s excellent tutorial Here.
1955pluralpluribusslidemachine doubling

 

 

Die Deterioration Doubling: A circumstance that occurs from die deterioration whereby the devices show a duplicate image on a coin. As metal must flow into the recessed areas of the die during the strike to form the devices on a coin, the edges and corners of the design elements on the die begin to wear. Eventually, this wear shows as a doubled image on the coins they strike. On Lincoln cents, the date and mint mark are often the first to show this doubling, since these devices are in the middle of a field with no other counter-relief to aid metal flow. Die deterioration doubling usually exhibits on the rim side of the devices, as in the example below. The 1955 “Poor Man’s Doubled Die” is NOT a doubled die at all, rather it is an example of die deterioration doubling. Dies in this time period were grossly “overused” resulting in many coins showing this common form of doubling. Die deterioration doubling is not generally considered collectible. Please see Jason Cuvelier’s excellent tutorial on the subject Here.
die deterioration doubling2 die deterioration doubling1

 

 

Split Plate Doubling (Split Line Doubling): This occurs only on copper-plated zinc cents struck from mid 1982 to the present. During the striking of plated cents, the plating is stretched in order to form the raised design elements. Whenever relief is created from a flat surface, there must be expansion of the overall surface area, thereby putting stress on the plating. Sometimes, the plating will split on the rim-side of the devices, exposing the zinc core. The exposure will be in the same shape as the design elements, thereby creating a “doubling” effect. The exposed zinc is blue-ish in color. In addition to the examples shown below, please also see Jason Cuvelier’s thread on the subject Here:
splitplatedoubling1 splitplating

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Section 2: Master Hub.  These are all common and hold no premium.

Reduction Lathe Doubling: This form of doubling occurred on several master hubs in the Lincoln cent series. Since master hubs were often re-used over a span of years, this type of doubling will show on EVERY cent struck over a period of years that the master hub was used, and therefore carries no premium. Some refer to this as “series doubling.” The Janvier reduction lathe was the machine that was used to transfer the image from the galvano to the master hub. There were 2 arms, one which traced out the image on the galvano, while the other cut a smaller version of the design onto the master hub. This would require many passes by the arm to do, and if there was a slight slip of the arm during the process, the design would be recreated in a slightly different place, creating this doubling. Some of the master hubs that had reduction lathe doubling on them were:
1. The 1909 reverse master hub, showing on the bottom of some of the letters in CENT and UNITED STATES OF AMERICA. This showed up for several subsequent years as well.  Images by Jallengomez.
1909 Reduction Lathe A 1909 Reduction Lathe B

 

2. The 1909 obverse master hub on the BE of LIBERTY and the W of We. The extra thin bar on the vertical of the B and the extra notches on the W can be seen spanning many master hubs and exhibits for many years until they were redesigned in 1955.

RLDonB

 

3. The 1933 obverse master hub and its successors used in 1935, and from 1937 until 1955, which showed a bold doubled forehead and front hair curl.
redlathefore1redlathefore2

 

Additionally, there are many master hub anomalies confined to individual master hubs. For example, from 1937 through 1942 (excepting 1938) the R in LIBERTY had a notch on the top left corner. This exhibits on all dies spawned from this master hub and is NOT the result of a chipped working hub.

 

 

Section3: Master Die. Again, these are common and hold no premium.

There were many engraving issues on master dies, which are often confused as hub doubling. (Reused master hubs had to have the last digit or two engraved into the master die.)

1. 1932 cents on the 32.  Photo courtesy of grnwavdav (David Miller)
32

An additional example is this doubled forehead, nose, and chin seen on 1946 cents.

 

 

 

 

 

 

 

 

 

There were many other cases of master die doubling, too numerous to demonstrate here, but the most often confused case is in 1972.  There were 2 master dies used this year, one showed “doubling” and one did not. Jason Cuvelier’s tutorial on this subject can be seen here.

 

Section 4: Working hub. Again, these are common and hold no premium.

Channeling (Trenching): On many Lincoln cents from the 1920s to the 1950s, we see an incuse “channel” surrounding parts or all of Lincoln’s bust. It is believed that many working hubs had this channel engraved around the bust, possibly in an effort to prolong the life of the working hub, or to sharpen the profile, although we are not certain of the reason. Once believed to be a master die issue, it is now more commonly believed to have been done on individual working hubs, as it shows inconsistently on coins within a given year.
MDO1943trench_zps13df464f

 

 

 

 

 

 

 

 

 

 

Section 5:  Doubling on errors. Unlike the other listed forms of doubling, these errors can carry  strong premium.

Grease Mold Doubling (Stiff Die Fill Raised Design Element Doubling): error-ref.com‘s term for a recently discovered form of doubling being found on cents from the mid to late 1990s, affecting the terminal digit of the date. In this term, the word “mold” is used as in “jello mold,” not as in “black mold,” or fungus. Presumably, a greasy/gunky film covering the die surface can become hard enough from the striking process that it forms a solid mold of the design element. If this solid mold of gunk begins to shift into the field from its original position, and since it is in the same shape as that portion of the die, it can create a raised design element in an offset position. Of course, since this mold will be somewhat smashed during the strike, the slightly raised element will be larger that the original design element. In addition to the link at the beginning of the entry, please also see this article by Mike Diamond for more information. The images below were donated by jallengomez and Joel.
Greasemolddoubling2 Greasemolddoubling1

 

Double Strike: A coin that failed to completely eject from the striking chamber and was therefore either partially or completely struck a second time. This should not be confused with Strike Doubling, which is another term for machine doubling.
1918_Doubled_Struck_Cent

 

Section 6: Doubling on the Mint Mark.

Broken Mint Mark Punch: Sometimes the punch that is used to make the mint mark on a working die can be damaged or broken. Each coin struck by these dies will also show these irregular mint marks. They can sometimes resemble a re-punched mint mark as is the case on this 1979D cent. This broken punch was used on many 1979D working dies.

79Dbrokenpunch

Section 7: Doubling from post-strike damage

Rippled Coin: This is a form of post-strike damage that causes a doubling (or multiple) effect on the devices. Just as the name suggests, the coin exhibits ripples on its surface, often following the contours of the devices giving them a doubled/tripled/quadrupled appearance. The exact cause(s) are unknown, but contact with an acidic substance is one theory. Photos courtesy of forum member Liz.
rippled-6rippled-7rippled-5

Will’s Playground

Abraded Die
Acid Job
Alloy
anvil die

annealed
bay
blank

blistered plating
blank

broad strike

brass plated cent
Brockage
business strike

bust
Cast Counterfeit
clash marks
clipped planchet
collar
counter-stamp

close AM
cud
device

die break
die cap
die chip
die clash
die crack
die dent
die deterioration
die deterioration doubling
die gouge
doubled die
dual mint mark
Early Releases
edge
egg nog
feeder finger
Feeder Finger Damage
FG
field
flow lines
galvano
garage job
greasy ghost
hammer die
incuse
initials
interior die break
Janvier reduction lathe
lamination
large date
machine doubling
master hub
mini-mule
mint luster
misaligned die

misplaced mint mark

mylar
no FG
notching
over mint mark
planchet
plating
post-strike damage
progressive indirect design transfer
proof
rim
ridge ring
serifs
small date
split serif
split plate doubling
Stripped Plating
struck through
Struck Through Filled Die
third party grading service
trails
transitional design variety
upset mill
VDB
wavy steps
wide AM
Wrong Design Variety

zinc rot

Glossary List S

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Welcome to the Lincoln Cent Forum Glossary.
Use the alphabetical links above to navigate to the desired term.
This glossary of terms was written and compiled by Will Brooks with the help of our forum members. A huge thanks to everyone who contributed knowledge, ideas, words, and photos to make this growing educational resource possible. Special thanks to Richard Cooper, aka “Coop” who donated many of the photos.

S Mint Mark: Cents struck at the San Francisco Mint bear an S mint mark below the date. Business strike Lincolns were struck at the San Francisco Mint from 1909 until 1974, except for 1922, 1933, 1948-1951, and 1956-1967. Also, starting in 1968 and continuing to the present, proof cents also exhibit the S mint mark. One notable exception is that in 1990, some proof sets contained a cent that was missing the S mint mark. These carry a strong premium. Please see Jason Cuvelier’s excellent tutorial on S mint mark styles Here.

Saddle Strike: When a planchet is far enough off-center out of the collar that two different adjacent die pairings strike it at the same time leaving two completely separate partial strikes on the coin. There area on the coin between the two strikes sometimes buckles upward resembling a saddle.
Saddle_Strike__image_by_Jfit

Sand Cast Counterfeit: See Cast Counterfeit.

Satin Finish: The mint has made several special issues of uncirculated and proof cents that have a “satin finish.” Special preparation of the dies give these cents less glossy fields. These special satin finish issues began in 2005 and ended in 2010. There was also a 1936 proof cent issue with a satin finish.
satinfinish

Seigniorage: This is the difference in the face value of a denomination and the actual cost to produce and distribute it. This is an important issue in the debate over continuing the production of Lincoln cents, and the potential materials that may be used in their future production.

Semi-key: The “2nd tier” of difficult issues in a series to collect due to rarity and price. The very most difficult to obtain are considered key.

Series: The complete chronological run of a particular denomination or sub-denomination. For example, the Lincoln cent series runs from 1909 until the present, while the wheat cent series runs from 1909 until 1958.

Series Doubling: See Reduction Lathe Doubling.

Serif: An extension, base, or flourish often seen at the end of , and coming off at an angle to, a letter stroke. Doubled dies and re-punched mint marks can often be identified by a split in a letter’s serif.
serif

Separation Lines: See Division Lines.

SG: See Initials.

Shattered Die: A die that has suffered one or more major rim-to-rim die cracks, with some displacement showing on the coins it strikes. Some of these could be considered major retained cuds. A shattered die is unlikely to last through many more strikes before completely breaking into pieces.

Shield Cent (Shield Reverse): A Lincoln cent minted from 2010 until the present, bearing a reverse design featuring a shield. This reverse design was created by artist Lyndall Bass, and sculpted by Joseph F. Menna, both of whose initials appear on the reverse of these cents.
shieldreverse

Shifted Hub Doubling: Also called a class 9 doubled die, this is strictly isolated to the single squeeze era. It is surmised that as the pressure increases during a single-squeeze hubbing, that die can slightly shift into its final position, leaving some doubling. Since blank dies are convex, class 9 doubling usually manifests on the central design elements, especially the 6th and 7th columns on the reverse of Lincoln memorial cents, and on the left hand of Lincoln on the Formative Years in Indiana reverse.
shiftedhubdoubling2 shiftedhubdoubling

Single Squeeze: Single-squeeze hubbings began experimentally in the 1980s and became the exclusive method for hubbing dies by 1996. Before that, dies had to be hubbed multiple times to get an acceptable image on them for striking coins. By hubbing a die in a single attempt, the mint hoped to eliminate doubled dies from happening. However, this method ended up creating a new class of doubled die called shifted hub doubling, or Class 9 Doubled Dies.

Slab: The colloquial term for the plastic holder that third party grading services put coins into after grading and/or attribution. The holder will generally have the coin’s grade and/or attribution number labeled on it.
slab1

Slide-type Machine Doubling: See Machine Doubling.

Small Date: In the Lincoln cent series there are 4 years that saw a mid-year design change in the font of the date, resulting in Large Date, and Small Date issue varieties released within those years. Those years are 1960, 1970 (S mint mark only), 1974, and 1982. Please see Jason Cuvelier’s excellent tutorial on the subject Here.

Special Mint Set: From 1965-1967, the mint did not issue any proof sets. They did, however, issue these “Special Mint Sets” during those years featuring a cent, nickel, dime, quarter, and half in a plastic holder. These were not proofs, but they were struck with specially prepared dies and under higher pressure creating very well-struck coins. Coins from these sets are often called “SMS” coins.

Specimen: Any individual coin, as an example of a particular issue variety, die variety, or error.

Spiked Head: The skull region of the bust on Lincoln cents is a common area for Die Cracks to develop. See also Cracked Skull. When these die cracks extrude out of the skull into the field, they are colloquially called “Spiked Heads.” Jean Cohen lists Spike Heads in her book “Errors on the Lincoln Cent.” Photo courtesy of forum member duece2seven.
spiked head

Split Die: A die that has been bisected by a rim-to-rim die crack that extends deep enough into the die to cause lateral displacement, leaving a gap in the die, which will show as a wide unstruck raised ridge on a coin.

Split Plate Doubling (Split Line Doubling): This occurs only on copper-plated zinc cents struck from mid 1982 to the present. During the striking of plated cents, the plating is stretched in order to form the raised design elements. Whenever relief is created from a flat surface, there must be expansion of the overall surface area, thereby putting stress on the plating. Sometimes, the plating will split on the rim-side of the devices, exposing the zinc core. The exposure will be in the same shape as the design elements, thereby creating a “doubling” effect. The exposed zinc is blue-ish in color. In addition to the examples shown below, please also see Jason Cuvelier’s thread on the subject Here:
splitplatedoubling1 splitplating

Split Serif: A doubling effect on the serif of a letter as a result of hub doubling or re-punching.
splitserif

Squeeze Job: See Garage Job.

Steel Cent (Steelie): A cent minted in 1943 which had a steel core plated with zinc. This was done due to a shortage of copper during World War II. A Steel cent should weigh 2.7 grams and be strongly attracted to a magnet. A large number of these cents were re-plated outside of the mint in an effort by people to make them look uncirculated. There were also a very small number of steel cents accidentally struck in 1944. Beware of re-plated copper cents and altered cents from other years. A re-plated copper cent may stick slightly to a magnet, but not with the same strength as a genuine steel-core cent.
steelie

Stiff Die Fill Raised Design Element Doubling: See Grease Mold Doubling.

Straight Clip: See Clipped Planchet.

Strike: The moment when the dies hit the blank planchet, thereby creating the design in relief on the coin.

Strike Doubling: See Machine Doubling.

Stripped Plating: When the copper plating is removed from the zinc core of a cent using chemical or mechanical means. This seems to be a popular science experiment in recent years. One must be careful to not confuse a stripped cent with a genuine unplated cent. The former is post-strike damage, while the latter is considered a mint error. A genuine unplated uncirculated cent will still have mint luster, while a stripped one will not. Also, some of the methods for stripping a cent, such as hammering it between leather to split the plating, will leave the cent with a larger-than-normal diameter, sometimes referred to as a “Texas cent.” For more information on stripped plating vs. unplated mint errors, see Jason Cuvelier’s tutorial Here.

Struck Counterfeit: A counterfeit coin made by using dies to strike blank planchets, as opposed to a cast counterfeit, which is made by pouring metal into a mold. To identify struck counterfeits, one must be very knowledgeable of the specifications and design attributes for that issue, since struck counterfeits will exhibit flow lines and a lack of pitting, just like a legitimately struck coin would.

Struck Through: A struck-though error happens when a foreign object gets between the dies and an unstruck planchet. When the dies strike the coin, the foreign object will also be struck into it, leaving an incuse impression in the coin. The “foreign object” may be anything, such as cloth, wire, grease, dirt, metal scraps, or even another coin which had stuck to one of the dies, called a die cap.

Struck Through Filled Die: The most common form of struck through, a cent that is struck though a filled die will have missing or weak design elements. Since that portion of the die is filled or clogged with grease or dirt, that portion of the design will not be struck on the coin. Although this can affect any portion of a coin, some of the more well-known instances in the Lincoln series are the 1922 “Weak D” cents, as well as some of the “no FG” cents.
1994struckthroughfilleddie greaser

Struck Through Late Stage Die Cap This is a coin that was struck by a capped die which has already struck many other coins. The face of the die cap gets thinner and thinner with each strike, as it expands outward. After striking so many additional planchets, the face of the die cap will be thin enough to allow parts of the normal die design to appear on the struck planchets, yielding a ghost-like image of the bust and other devices. As the die cap continues to strike coins, more and more of the normal design elements will show on the struck coins until the die cap completely deteriorates away. Photos courtesy of forum member Joel.
196_ Obv.196_ Rev

Sunken Die: See Die Subsidence.

Superb (BU): A subjective term referring to the highest end of the mint state scale (MS 67+). “Gem” is higher than “Choice,” and “Superb” is higher than “Gem.”

Glossary List X-Z

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MNOPQ-RSTUVWX-Z

Welcome to the Lincoln Cent Forum Glossary.
Use the alphabetical links above to navigate to the desired term.
This glossary of terms was written and compiled by Will Brooks with the help of our forum members. A huge thanks to everyone who contributed knowledge, ideas, words, and photos to make this growing educational resource possible. Special thanks to Richard Cooper, aka “Coop” who donated many of the photos.

Zinc: An element used as the core material in copper-plated zinc cents minted from mid-1982 until the present. Zinc was also used as the plating over steel cents made in 1943, and also as an additive in some copper-alloy cents prior to 1982. See Alloy for compositional break-downs of Lincoln cents.

Zincoln: A colloquial term used for copper-plated zinc Lincoln cents minted from mid 1982 until the present.

Zinc Rot: Zinc corrodes easily when exposed to the environment. When the plating is split on a copper-plated zinc cent, the zinc will often corrode under the plating, and push up on it creating a bigger and bigger fissure. Due to the strength of many of the hand-punched mint marks on pre-1990 business strike cent dies, this is a very common place on Lincoln cents for the plating to split and for this corrosion to take place.
zinc rot

Glossary List P

ABCDEFGHIJKL
MNOPQ-RSTUVWX-Z

Welcome to the Lincoln Cent Forum Glossary.
Use the alphabetical links above to navigate to the desired term.
This glossary of terms was written and compiled by Will Brooks with the help of our forum members. A huge thanks to everyone who contributed knowledge, ideas, words, and photos to make this growing educational resource possible. Special thanks to Richard Cooper, aka “Coop” who donated many of the photos.

Pareidolia: The phenomenon where people see patterns or objects in otherwise random data. People often “see” extra design elements that aren’t really there in a coin’s damaged areas, plating blisters, stains, etc.

Partial Collar Strike: This occurs when a coin is struck which its edge only partially contained in the collar. The part of the edge which is contained in the collar is constricted from expansion as normal, but the portion not contained in the collar expands abnormally as a broad struck coin would. This creates a bi-level edge which resembles the wheel of a railroad car, and thus these are colloquially called “railroad rims.” This is somewhat of a misnomer, however, since the edge is really the part showing the effect, more so than the rim. Photo examples pending.

Pattern Coin: A prototypical coin produced with a design that has not yet been approved for mass-production and release.

PDS System: The PDS System is a highly structured cataloging system for mint varieties and errors. It was originally compiled by Alan Herbert in 1971. PDS stands for the three main divisions of the minting process: “planchet,” “die” and “striking.” Two more divisions cover collectible modifications after the strike, as well as non-collectible post-strike modifications such as altered, counterfeit and damaged coins. Thank you to forum member 2Old for writing this entry.

Penny: A British coin with a face value of 1/100th of a pound. Also, the colloquial term commonly used for the U.S. cent.

Phantom D: In 1997, a new master hub with a D mint mark was made and used in 1997, 1998, and 1999.  A master die was made from this hub bearing the D mint mark for producing working hubs and dies for the Denver mint.  Then, the mint ground the D off of the master hub and created another master die without the D for producing Philadelphia working hubs and dies. However, the removal of the D from the master hub was not perfect and on uncirculated coins minted during these years, especially 1999, remnants of this D mint mark can be seen on the cents. It can be very faint and difficult to see, but is commonly found on cents in 1999 mint sets.  Please see Brad Podraza’s tutorial Here for further information and illustration.

Pick-up Point: Any of the specific attributes or markers on a particular variety coin used to identify the variety itself. For example, a pick-up point may be a split serif, or an elongated dot, or some other particular marker.

Pivoted Hub Doubling: Also called a class 5 doubled die, pivoted hub doubling is the result of a 2nd hubbing of a die which was rotated clockwise or counterclockwise from a pivot-point near the rim, thereby creating stronger doubling near the opposite part of the rim. This differs from a class 1 doubled die, which has its point of rotation at the center and therefore equally strong doubling around the entire rim. The 1995 1DO-001 is an excellent example of class 5 doubling. With the pivot point at K-5, there is little to no doubling visible at the date, but it is strongest near the opposite part of the rim on LIB and IN GOD. Please see Jason Cuvelier’s excellent tutorial on the subject Here.

Planchet: A modern spelling of the word planchette, which is French for “little plank.” This is the word for an unstruck metal disc, after it has had its proto-rim created in the upset mill, and before being struck into a coin. Prior to its entry into the upset mill, it is called a blank.
Blank-Planchet-plating-struck_coin_IMAGE__biokemist6

Plating: On Lincoln cents, the plating refers to the thin copper coating covering the zinc core on cents made from mid 1982 to the present, or to the thin zinc coating covering the steel core on 1943 cents. Other than this, cents were made from a solid copper-alloy. (See Alloy for compositional breakdowns) Additionally, sometimes people plate or re-plate Lincoln cents outside of the mint to give them a gold or silver or uncirculated appearance. This is considered post-strike damage.

Plating Bubbles (Blisters): See Blistered Plating.

Polishing: See Abraded Die.

Polyvinyl Chloride (PVC): A plastic which, among many other uses, is sometimes used for coin storage products, such as flips. Coins kept in vessels containing PVC will accumulate a greenish residue, ruining the coin. Take care to use materials made from mylar for long-term safe storage of your coins.

Poor: A coin grading standard of 1. See our grading guide Here.

Poor Man’s Doubled Die: See Die Deterioration Doubling.

Population Report: The number of specimens holdered by each individual third party grading service of a given coin issue or variety.

Post-mint Damage: This term is no longer preferred. Please see Post-strike Damage.

Post-strike Damage: This term is now preferred over Post Mint Damage. This is any damage that happens to a coin after the moment it is struck, including contact marks the coin may suffer before leaving the mint from falling into hoppers, or being bagged, etc. Of course, anything that happens to the coin during its life-span in circulation also falls into this category, such as purposeful or accidental hits, corrosion, unnatural toning, etc.

Pre-strike Damage: Damage to a blank or planchet that happens before it is struck by the dies.

Presidency in Washington D.C.: The fourth of four reverse design variations on 2009 Lincoln cents made to commemorate its 100th anniversary. This is also known as LP-4. This reverse was designed by Susan Gamble and sculpted by Joseph F. Menna.
PresidencyLP4

Professional Life in Illinois: The third of four reverse design variations on 2009 Lincoln cents made to commemorate its 100th anniversary. This is also known as LP-3. This reverse was designed by Joel Iskowitz, and sculpted by Don Everhart.
professionallife

Progressive Indirect Design Transfer: A form of die deterioration that manifests itself in the form of a “ghostly” image of a design element on the opposite side of a coin. The force of a die strike travels through the planchet and into the opposite die. After hundreds of thousands of strikes, the outline of the designs begin to transfer to the opposing die and show on the coins that are struck. In the case of Lincoln cents, it is common to see a ghostly outline of Lincoln’s bust on the reverse of wheat cents that are struck in later die states. It is especially visible on uncirculated coinage. This should not be confused with a die clash or a “greasy ghost.”  First photo courtesy of forum member TJ1952.

S20160130_009PIDT

Proof Coin: Unlike a business strike coin, which is used for everyday transactions and purchases, a proof coin is a specially made coin solely for collecting purposes. A proof coin is made from specially prepared dies and striking processes which result in a coin with stronger, crisper devices, sharper rim, and in the case of modern proofs, mirror-like surfaces, and frosted-looking devices. Also, since proof dies are extremely limited in the number of coins they may strike, proof coins will not exhibit the signs of die deterioration. Proof coins come in specially-made packaging from the mint.
cameo

Proof Set: A group of proof coins, usually all of the different denominations from the same year, packaged and sold by the mint for collectors.

Proof-like: This refers to a business strike coin that has unusually nice features similar to what a proof coin would have.

Proto-rim: The raised perimeter on both faces of a coin that is produced by the upset mill on a planchet before being struck. The striking process alters the shape of the rim, flattening it out.

Punch: See Mint Mark Punch. There were no date punches used in the Lincoln cent series.

Push-Type Machine Doubling: See Machine Doubling.

Glossary List Q-R

ABCDEFGHIJKL
MNOPQ-RSTUVWX-Z

Welcome to the Lincoln Cent Forum Glossary.
Use the alphabetical links above to navigate to the desired term.
This glossary of terms was written and compiled by Will Brooks with the help of our forum members. A huge thanks to everyone who contributed knowledge, ideas, words, and photos to make this growing educational resource possible. Special thanks to Richard Cooper, aka “Coop” who donated many of the photos.

Railroad Rim: See Partial Collar Strike

Raised: Any device or anomaly or a coin in positive relief above the field surface of a coin. This is the opposite of incuse.

Raw: Refers to a coin that has not been graded, attributed, and holdered (slabbed) by a third party grading service.

RDV-006: Varietyvista.com’s assigned number for the Lincoln cent’s reverse design designated for use on business strike cents from 1989-1992, and on proof cents from 1989 until 2008, excepting 1993. This is a notable variation because it also appeared on the reverse of some 1988 business strike cents (a transitional design variety known as ’88 reverse of ’89) and also on the reverse of some 1998, 1999, and 2000 business strike cents. (Wrong design varieties called wide AMs, due to the wider space between the A and M of AMERICA.) Please see John Miller’s excellent tutorial Here.

RDV-007: Varietyvista.com’s assigned number for the Lincoln cent’s reverse design designated for use only on business strikes from 1993-2008, and proof cents in 1993. This is a notable variation because it also appeared on the reverse of some 1992 business strike cents, as well as some 1998 and 1999 proof cents, known as close AMs or CLAMs, due to relative closeness of the A and M in AMERICA. (See also Transitional Design Variety and Wrong Design Variety.) Please see John Miller’s excellent tutorial Here.

Re-plated: Although any cent can be re-plated, this is most often seen on 1943 cents. The zinc-plated steel was frequently re-plated with various metals in an attempt to make them look uncirculated. This is considered post-strike damage and devalues the coin. A coin that has been plated or re-plated outside the mint will not have radial flow lines, be lacking mint luster, may show bubbling or pooling of metal especially along the devices, and be off color.
replated

Re-punched Date: The practice of punching the date into the die ended in 1908; therefore, there are no re-punched dates in the Lincoln cent series.

Re-punched Mint Mark: On Lincoln cent business strikes, the mint marks were punched by hand into the Working dies up through 1989, and on proof coinage until 1985. Sometimes a punch contacted the die more than once; sometimes purposefully due to the first punching being unsatisfactory, or sometimes accidentally due to the punch bouncing or skipping during the initial hit. If subsequent hits by the punch did not line up exactly with previous punchings, a secondary mint mark would be created on the die and all the coins it struck. Most of these re-punchings were just slightly rotated from the first, and can be identified by noting split serifs. Many publications call these “tilted” rpms, but “rotated” might be a better term, since a punch could also be tilted on an angle of incidence into the die.
1960rpm1b

Red: The original mint color of a Lincoln cent. Cents naturally turn brown from exposure to environment and circulation. Third-party grading services denote a cent as “red,” “red/brown,” “or brown.”

Red Book: Also known as A Guide Book to U.S Coins, the Red Book is a most popular resource for coin values and information.

Red/Brown: A color designation used by third-party grading services to denote a coin that still has some original mint “red” color, but is starting to turn “brown” from environmental and circulation exposure.

Reduction Lathe Doubling: This form of doubling occurred on several master hubs in the Lincoln cent series. Since master hubs were often re-used over a span of years, this type of doubling will show on EVERY cent struck over a period of years that the master hub was used, and therefore carries no premium. Some refer to this as “series doubling.” The Janvier reduction lathe was the machine that was used to transfer the image from the galvano to the master hub. There were 2 arms, one which traced out the image on the galvano, while the other cut a smaller version of the design onto the master hub. This would require many passes by the arm to do, and if there was a slight slip of the arm during the process, the design would be recreated in a slightly different place, creating this doubling. Some of the master hubs that had reduction lathe doubling on them were:
1. The 1909 reverse master hub, showing on the bottom of some of the letters in CENT and UNITED STATES OF AMERICA. This showed up for several subsequent years as well.  Images by Jallengomez.
1909 Reduction Lathe A 1909 Reduction Lathe B

2. The 1909 obverse master hub on the BE of LIBERTY and the W of We. The extra thin bar on the vertical of the B and the extra notches on the W can be seen spanning many master hubs and exhibits for many years until they were redesigned in 1955.
RLDonB MDOontheW

3. The 1933 obverse master hub and its successors used in 1935, and from 1937 until 1955, which showed a bold doubled forehead and front hair curl.
redlathefore1redlathefore2

4. The D of God had “doubled” vertical bar starting with the 1922 Master Hub and continuing until the mid 50s.
MDOontheD
Relief: In numismatics, relief refers to the difference between the high and low points in the coin’s design elements. However, when preceded by the word “in,” as in “the anomaly is in releif,” it usually means raised.

Retained Cud: This is a rim-to-rim die break that hasn’t completely fallen out of the die. There is usually some lateral or vertical shifting of the broken piece, which will show on the coins it strikes, although the design will be largely intact in that broken area on the coin itself.  Please visit cuds-on-coins.com to see listings for retained cuds.
1943retainedcudD 1943retainedcudC 1943retainedcudA

Retained Interior Die Break: This is an interior die break that hasn’t completely fallen out of the die. Since the piece hasn’t fallen completely out, some design elements may still be seen in the area on the coins it strikes, even though there may be lateral or elevation shifts. Please visit cuds-on-coins.com for listings of retained interior die breaks.  Photos donated by Bella.
retiainedIDB1 retainedIDB2

Retained Lamination: This is simply a lamination peel that is still attached to the coin.
1958Dlamination

Retained Struck-through: This is simply a struck through error where the foreign object is still attached to the coin.
retainedstruckthrough2retained_struck_through_wire_includedretainedstruckthough3

Reverse: The side of a coin commonly referred to a the “tails” side and bears the secondary design. It is the opposite side of the obverse. On Lincoln cents, there have been 7 different major reverse designs used.
The “Wheat” reverse from 1909-1958.
The “Memorial” reverse from 1959-2008
The “Birth and Early Childhood in Kentucky” reverse used only in 2009
The “Formative Years in Indiana” reverse used only in 2009
The “Professional Life in Illinois” reverse used only in 2009
The “Presidency in Washington D.C.” Reverse used only in 2009
The “Shield” reverse used from 2010 to the present.
(See individual listings for each of these issues for more information.)

Reverse Design Variety: Any of the minor or major reverse design changes over a series’ run. The RDV# designations commonly used for Lincoln cents are proprietary to (and can be seen at) varietyvista.com.

Riddler: A sifting device which removes both oversized and undersized coin blanks, planchets, or coins, allowing only the proper sized ones to continue on in the coin production process. Also, one of the arch-enemies of Batman.

Ridge Ring: One of the many manifestations of die deterioration, a ridge ring is a circular area of distortion that goes around the perimeter of a coin near the rim and is the result of cold-metal flow toward the rim from the striking process. These are most commonly seen in the 1980s.  Photos courtesy of jay4202472000.
ridgering1 ridgering2

Rim: The rim is the raised part of a coin that encircles the perimeter on the obverse and reverse of a coin. A proto-rim is created by the upset mill and the finished rim we see on a coin is completed by the striking process. Do not confuse this with the edge of a coin.
rim

Rim Burr: This is a form of pre-strike damage to the rim caused by the feeder finger, whereby a portion of the proto-rim is “sliced” or “gouged” up and subsequently struck into the coin face. The burr can be still partially attached to the rim, or can be completely detached and struck into the coin face in any location and orientation. Many of these are being found recently on shield cents. Photos courtesy of forum member Jacob.
OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERA

Rim Cud: A cud appearing only on the rim of a coin and is the result of a part of the die’s rim gutter being broken off.
rimcud

Rippled Coin: This is a form of post-strike damage that causes a doubling (or multiple) effect on the devices. Just as the name suggests, the coin exhibits ripples on its surface, often following the contours of the devices giving them a doubled/tripled/quadrupled appearance. The exact cause(s) are unknown, but contact with an acidic substance is one theory. Photos courtesy of forum member Liz.
rippled-5rippled-7rippled-6

RM: See Initials.

Rockwell Hardness Test: A test done at the mint to determine if a planchet or die is of appropriate hardness. The test involves pressing a small metal ball into the planchet or die and measuring the depth of the resulting cavity. This smooth round or oval cavity can be sometimes seen on struck coins. Please visit this link for more information and photo examples. http://conecaonline.org/content/RockwellHardnessTest.html

Roll: A determinate number of coins of a like denomination held in a paper wrapper. A full Lincoln cent roll has 50 cents in it.

Rolled Thin (or Thick) Planchet Stock: The sheet metal from which coin blanks are cut can sometimes be off-spec, being too thin or too thick. Coin blanks cut from rolled-thin stock will result in an thinner, underweight coin and, because of its thinness, may not receive a full strike. A coin blank cut from rolled-thick stock will be thicker and overweight. A cent should be 1.52 mm thick. Copper-alloy cents should weigh 3.11 grams, and copper-plated zinc cents should weigh 2.5 grams.

Roller Lines: These are very thin parallel striations, often seen on both the obverse and reverse going in the same direction. Though sometimes blamed on improper alloy mixture, these thinner, more even lines are more likely from dirty or damaged rollers from the rolling mill when it was reducing the planchet stock to the correct thickness for coin production. More commonly seen in the late 70s and early 80s. Photo courtesy of jmangham.
roller lines

Rotated Die Strike: This is when a coin is struck by dies that are out of correct rotational orientation with respect to each other. When you turn a normally orientated U.S. coin over in a “north to south” or “top to bottom” direction, the design on the opposite side should now also be correctly oriented for viewing. This will not be the case if the dies are out of rotation. The mint tolerance for die rotation is 15 degrees, but coins with struck by rotated dies don’t start to command a good premium until the die rotation is much greater than that. There are several instances in the Lincoln series with the most well-known being a 1994 with 165 degree rotation.  Below is a 1994 with 165 degree rotation, and a 1910 showing 90 degree rotation.  Photo of the 1910 courtesy of forum member duck620.
rotated94 rotateddies

Rotated Hub Doubling: Also called a class 1 doubled die, this type of hub doubling results in the most dramatic and coveted of doubled dies. This occurs when a second hubbing of a die is rotated either clockwise or counterclockwise from the first, from the center point of the die, thereby creating equally strong doubling around the entire perimeter of the coin face of the coins it strikes. The most well-known doubled dies in the Lincoln series (and in the entirety of numismatics) are class 1, such as the 1969S 1DO-001 and the 1955 1DO-001. Please see Jason Cuvelier’s excellent tutorial on the subject Here.

Let’s Talk About Doubling

This is going to be a tutorial on the 4 main types of doubling you will encounter in your searches, and how to tell them apart.

First, let me explain what a doubled die is, and what it is not.

-A doubled die occurs during the hubbing process of the dies. Up until the mid-1990s, dies were hubbed multiple times using the “multi squeeze” method. The die blank which is was to be hubbed was placed at the bottom of the “hubbing chamber”, with the working hub (depicting the image to be transferred onto the working die) sitting above it. When the chamber was activated, the working hub would descend onto the die blank with hundreds of tons of force to transfer the image. At the time, one single hubbing was not strong enough to transfer a perfect image in one squeeze, so the die was removed and put into an oven to soften the steel and allow a better design transfer for the next squeeze. Once the die is finished annealing, it is returned to the chamber for additional hubbings. HERE IS THE IMPORTANT PART. If for some reason the die and the hub are not properly aligned, when the image is again transferred, it will not line up exactly from the initial impression, resulting in a doubling of the image on the die. There are 3 main classes of doubled die directly caused by the failure of a perfect alignment between the die and the hub.

Class I (rotated): This occurs when the die and hub are lined up correctly on the X and Y axis, but the die has been rotated about its center either clockwise or counter-clockwise. Famous examples include the 1955, 1969-S, and 1972 doubled dies.
Class IV (offset): this occurs when the die is offset from the hub along the X and Y axis. Doubling will appear to go in one single direction. Famous examples include the 1983 DDR and the 1984 doubled ear.
Class V (pivoted): similar to class I doubled dies, class V only differ in that the pivot point is elsewhere on the coin besides the center. This means that the doubling will be weakest at the point of the pivot and will be strongest directly across from the pivot point. Well-known examples include the 1995P-1DO-001 (pictured below).

Since the die itself is doubled, that means that ALL COINS STRUCK BY THE DIE WILL SHOW THE SAME DOUBLING, not taking into account die state and post-strike damage.

Now, what a doubled die is NOT.
-A doubled die IS NOT a coin that is struck twice when being minted. This is a common misconception for beginners, and I admit that I thought this was what a doubled die was when I first started out.

If you wish to learn more about the hubbing process as well as additional classes of doubled dies, feel free to visit doubleddie.com for more information.

Now we will go over what to look for in your searches.
The main things you should be looking for on coins is notching and separation lines. These two indicate that the hubbing was not correctly aligned. Since there would be 2 sets of letters if we were looking at “IN GOD WE TRUST”, they would overlap at certain points and create notching at the corners.
Below is an example of 1995P-1DO-001…a class V doubled die with the pivot point around the date. This means that the doubling will be strongest opposite of the date; the motto above Lincoln’s head. The black arrows point to the notching in the letters while the red arrows point to the separation lines. I would urge anyone searching for doubled dies to purchase an example of 1995P-1DO-001 as they are inexpensive, dramatic, and will show you what to look for.


The second type of doubling you will come by, and quite possibly the one most confused for a doubled die, is machine doubling.
Machine doubling has nothing to do with the hubbing process, and takes place in the coin striking chamber. As the hammer die comes down to strike the coin, it may bounce or shift slightly if the die was installed loosely. This flattens parts of the design. This is what gives machine doubling its Flat and shelf-like appearance. A good indicator of machine doubling is if both the date and mintmark show doubling in the same direction, as doubled dies and repunched mintmarks have had nothing to do with each other up until recently. Here is an example of a machine doubled 1944-S cent. The red arrows point out the areas on doubling. Notice that the mintmark is doubled as well, and the doubling is flat and shelf-like.

The third type of doubling is most commonly found on wheat cents of the 1950s. Commonly titled a “poor man’s doubled die”, this anomaly is not a doubled die at all. Rather, it is die deterioration doubling, caused by the overuse of dies. Notice how the doubling is more ghost-like than an actual doubling of the design. The anomaly is not full like a doubled die is, and is often limited to the last digit of the date.

The last type of doubling I will go over is split-plate doubling. Found exclusively on cents with a zinc core and copper plating (all cents 1983 and on), this form of doubling can often be found on the dates of early 1990s cents, and on the reverse of many cents as well. Split -plate doubling occurs when the copper plating on the coin splits open around certain design elements, revealing the zinc below. They can be identified by the appearance of exposed zinc and a rippled appearance that is found almost exclusively at the tops of letters if you are looking on the reverse.

Sorry for the very long post, but I wanted to make sure to cover all the bases I felt needed to be covered. I hope this helps a lot of people in their coin roll searches, and that beginners will be able to more easily identify certain types of doubling.
Don’t be discouraged if you don’t find a doubled die immediately…my average is about 1 in 2500 cents if I am bankroll searching.
Remember…have fun and keep up the hunt!

Simon

 

I wanted to expand on Simon’s awesome thread here with a few more things that are often mistaken for hub doubling, but aren’t. I have recently seen several threads involving these issues and thought this would be the perfect place to add this little tutorial. These are just a few of the many examples of these and I just selected some of the more commonly noted and asked-about examples. This is by no means a comprehensive list.

First I would like to talk about what I will call design anomalies. In other words, these are things sometimes confused for hub doubling, which are really just a part of the design spanning MORE THAN ONE master hub, also called series doubling. For example:

1. The D of God had “doubled” vertical bar starting with the 1922 Master Hub and continuing until the mid 50s. I have seen this noted as part of the doubling on a doubled die, but really it is a normal part of the “design.”

2. The W in We has a strong notch on the right arm and a lesser one on the left arm beginning in 1909 and continuing all the way to 1955. Again, I have seen this noted as hub doubling, but it is normal for this span of dates.

There are others, but these were the two that I see questioned the most.

Secondly, there are many master hub anomalies confined to individual master hubs. For example, from 1937 through 1942 (excepting 1938) the R in LIBERTY had a notch on the top left corner. This is normal for all dies spawned from this master hub and is NOT the result of a doubled working die.

Thirdly, there are engraving issues on master dies, which are often confused as hub doubling. (Reused master hubs had to have the last digit or two engraved into the master die.)

1. This engraving doubling is often misconstrued as a doubled die on 1960 small date cents.

2. All 1965 cents show this notch on the 5.

3. All 1973 cents show this notch on the 3.

4. 1941 cents on the 4

5. 1944 cents on the 44

6. 1940 cents on the 40

Next, let us look at an issue many now believe to be from work done to working hubs during the 30s, 40s, and early 50.
A “trench” was added around the bust on many working hubs, perhaps in an effort to prolong the life of the working dies.
This trench is often mistaken for hub doubling. It is common for this era. It looks like this.

Additionally, we all have the doubled master dies to keep us on our toes. Please see Jason’s excellent tutorial on the 1972 doubled master die Here.

An additional example is this doubled forehead, nose, and chin seen on 1946 cents.

I am not sure what caused 1957 cents to look like this on GOD WE, but this is how the letters look on all 1957 specimens including the proofs. Here is a proof example.