Coin Terms and Definitions
When conversing with dealers or coin collectors you may be required to understand a limited amount of coin terminology. Although this listing of coin terms is not all comprehensive, it should assist with questions that you may have concerning the material used in this book and help you avoid confusion when trying to convey the details of a particular coin.
“D” — The Mintmark representing coins struck at the Denver Mint (and gold coins struck at Dahlonega from 1838–1861).
“S” — The Mintmark representing coins struck at the San Francisco Mint.
“P” — The Mintmark representing coins struck in the Philadelphia Mint.
Alloy — A combination of two or more metals fused together in the molten state. For example: bronze is an alloy of copper, tin and zinc.
Alteration — A coin that has been changed or altered to appear other than normal, with or without intent. Alterations usually represent pieces modified for jewelry or as novelty items but also include items altered with the intent to defraud. Double-headed magician’s coins and cutout coin jewelry are examples of jewelry or novelty items. A 1944-D cent with the first 4 shaved into a 1 to appear as a rare 1914-D is an example of a coin altered to defraud.
American Numismatic Association (ANA) — The world’s foremost organization promoting numismatic education. Open to dealers, collectors and researchers.
BIE — Reference given to a die break that occurs between the letters of B and E of LIBERTY on Lincoln cents when it takes on the appearance of an I and spells “BIE.”
Blank — The disc of metal that will be processed further to have its edge raised (at which point it is referred to as a planchet), and then struck into a coin. See Planchet.
Brass — An alloy of copper and zinc.
BREEN # — Reference numbers assigned to individual coins by date, Mintmark and type (and some varieties) in Walter Breen’s Complete Encyclopedia of U.S. & Colonial Coins. (to 1996)
Bronze — An alloy of copper, tin and zinc.
Business Strike — A coin intended for circulation or public use or one struck in that manner.
Central Design — The main theme of a coin’s design. For example, the portrait of John F. Kennedy is the central design on the obverse of the Kennedy half dollar, while the eagle is the central theme on its reverse.
Cherrypick — To find or purchase a rare variety that is unknowingly offered as a more common type.
Circulated — The presence of wear on a coin from circulation.
Clad — A planchet comprised of several layers of various metals bonded together into a single unit. Our current dimes through halves are clad coins comprised of a core of pure copper and layers of copper-nickel (75% copper and 25% nickel) bonded to either side.
Combined Organization of Numismatic Collectors of America (CONECA) — An organization dedicated to the study and education of error and variety coins.
Collar — The die that encircles the planchet at the time of striking. It restrains the outward flow of metal to assure the coin’s round shape is maintained and it forms the reeded edge on coins that bear that device. This often overlooked die can also be the subject of die varieties and errors.
Collar Clash — See Die Clash.
Copper-Nickel — An alloy of copper and nickel.
Counterfeit — An unauthorized coin, struck, cast or otherwise created to pass as a genuine coin.
Counter-Clash — A form of Die Clash resulting in the transfer of design elements from one side of the coin to the other, i.e., obverse design seen on the reverse of the coin.
Cross Referencing — Providing listing numbers assigned outside of the body of work in which they are given, to aid the reader in finding more information on that variety in other works.
Cud — See “Major Die Break.”
Designer — Person who creates the design used for a coin, medal or token.
Devices — The elements that make up a design. The “Central Design,” stars, lettering and date are all “devices.”
Die — A cylindrical bar of steel that has the design of a coin impressed into it incuse and which is used to strike coins.
Die Blank — A cylindrical-shaped piece of steel used to make dies and hubs.
Die Chip — A small, irregular cavity on the die resulting from a small chip. This results in a small raised area on the coin.
Die Clash (Die Clash Marks) — Marks on either or both dies that are the result of a planchet failing to enter the striking chamber and the dies smashing or “clashing” into each other. An upper die may also strike the edge of a collar resulting in the so-called double rim or on coins with reeding—evidence of reeding damage on the rim. Clash marks are very common and unless very strong, not normally worth premiums.
Die Crack — A split or crack in the face of a die, resulting in a raised, irregular ridge on a coin.
Die Gouge — A raised area on the die that is the result of damage caused by a gouging action from engravers’ tools, ejection mechanisms, awls or anything that results in a gouge in a die.
Die Life — The length of time a die remains in use, generally measured by the number of coins produced before being retired. Usually reported as estimates based on the average die life for a particular denomination in a given year or era.
Die Making Process — The entire process leading up to and including the making of a die. This includes the production of master tools, lathing operations, hubbing, heat treat, polishing and other finishing operations leading up to a usable die.
Die Marker — Any identifiable mark on a die that helps to identify or distinguish it from others; usually in the form of die scratches, cracks, chips, etc., that are associated with a particular variety.
Die Scratch — Fine lines scratched into a die; usually the result of abrasives used to clean up or dress-out dies such as wire brushes, stones, aluminum oxide cloth, etc., or from contact with a sharp instrument. These lines will be raised on the coin.
Die Stage — Designates changes in the die such as die chips, scratches, cracks, clashes, etc. Usually documented in the order in which they occur by letters appended to listing numbers.
Die State — Describes the age of a die based on a variety of diagnostics including: sharpness of devices, die flow lines and die deterioration. Ranges from “very early die state” (VEDS) to “very late die state” (VLDS).
Die Trails — A form of doubling related to the single squeeze minting process. The doubling presents as “die trails” and “wavy steps” on Lincoln cents. This form of doubling is actually an extension of the design elements.
Die Variety — Any variation in a coin’s design, resulting from an intentional change or mishap during its production or use. The term is generally restricted to variations that are considered “collectible.”
Double Denomination — A coin that has been struck by the dies of two different denominations such as a Roosevelt dime that has been struck a second time by Lincoln cent dies.
Doubled Die Obverse or DDO (Hub Doubled Die) — Refers to a coin struck with an obverse die that was doubled during its production via the hubbing process. See the chapter on doubling.
Doubled Die Reverse or DDR (Hub Doubled Die) — Refers to a coin struck with a reverse die that was doubled during its production via the hubbing process. See the chapter on doubling.
Dual Mintmark (DMM) — A relative of the OMM, the DMM refers to a coin with two different and completely separate mintmarks. See the 1980-D&S.
Early Die State (EDS) — Condition of the die shortly after it begins to show indications of use. See Die State.
Engraver — Person or machine that engraves or touches up dies.
Field — The area of the obverse or reverse that contains no design; background. It may be textured or smooth.
Error — Loosely defined as any coin struck on a defective planchet or struck with dies containing an error or mechanically mis-struck in error or a combination of the above.
Metal Flow Lines — Radiating lines on the surface of a die or coin created by the natural outward flow of metal eroding the die. Metal flow lines become progressively heavier as the die sees use. These lines are often removed (or partially removed) several times during the life of a die via die dressings with abrasives.
Specks — Small carbon spots (more often than not on copper coins) often caused by moisture.
Grade — The condition of a coin based on many factors including: wear (for circulated coins), luster, marks, strike, color and eye appeal.
High Point — Highest point of detail on a coin. This is normally the first area to show signs of wear.
Incuse — Refers to a sunken design that is lower than the surface of the field or other area in which it is found. Opposite of “relief” or “raised.”
Lamination — The layering, peeling or flaking of metal on a coin due to trapped slag, gases or other impurities being trapped in the metal at the time the ingots were formed (from which the coinage strip was made).
Legend — The inscription(s) other than the date and denomination found on a coin.
Major Die Break (Cud) — A broken die involving a piece that breaks from the shank and extends inward into the design. The result is often what appears to be a blob of raised metal in the area where the broken chunk of die fell out and a corresponding area of weakness on the side opposite the cud. Cud is a nickname taken from the appearance of the blob looking like a “cud” of tobacco held in at the side of a chewer’s mouth. Cuds may be found on the obverse, reverse or on the edge (collar die). Small cuds extending no further than the rim are referred to as “Rim Cuds.”
Master Die — Die created from the master hub and used to produce working hubs.
Master Hub — A hub used to produce master dies.
Mint Error — See Error.
Minting Process — The entire process leading up to and ending at the time the coin is struck. This includes: the designing of the coin, the production of master tools and dies, all phases of planchet production and the actual striking of the coins.
Mint State (MS) — An uncirculated coin without wear; as struck. May be naturally toned by time or be brilliant.
Mintage — Number of coins struck for a given date and denomination or variety (when known).
Mintmark Punch — A hand tool used for punching the mintmark into a die.
Mintmark — A letter punched into a die to indicate the Mint or origin. For example, the presence of a “P” below the date on a Roosevelt dime indicates it was struck by the Philadelphia Mint. Mintmark locations can and do often vary on the same denomination.
Misaligned Die — (See Clashed Die) A clashed die error that is struck off-center when compared to the opposite side of the coin.
Multiple Variety (or multiple error) — A coin that features more than one type of die or minting variety or error.
Nicks or Bag Marks — Contact marks in the form of abrasions, nicks and scratches on a coin caused by the coins falling upon each other (into tubs) during ejection from the presses and/or contact with each other while in shipping bags.
Numismatics — The study and collecting of coins, medals and tokens.
Obverse — The front or face side of the coin. Sometimes referred to as the “heads” side of the coin.
Off Metal Error — A coin that is struck on a planchet of the wrong composition than intended for a particular denomination. A cent struck on a dime planchet is an “off metal error.” This category also includes U.S. coins struck on foreign planchets of the wrong alloy.
Over Mintmark (OMM) — Refers to a coin that has two different mintmarks punched one over another. For example the 1944-D/S cent with the D punched over an S is an OMM.
Oxidation — Tarnish or oxides on the surface of a coin from exposure to the environment.
Planchet — A blank that has had its rims raised via the upset mill and any other processing necessary to make it ready for striking. Often erroneously referred to as “Type-2 Blank” or the redundant “Type-2 Planchet.”
Proof — A coin struck several times on a high tonnage press with specially polished dies on heavily burnished blanks for collectors. Often has highly reflective “mirror-like” fields and contrasting satiny designs.
Relief — Any design element that is raised above the field of the coin. Opposite of “incuse.”
Repunched Mintmark (RPM) — Any coin that shows multiple images of its mintmark as a result of repunching. See the chapter on doubling.
Reverse — The back side of a coin. Also referred to as the “tails” side.
Rim Cud — These are much more common than major Cuds and normally do not constitute a premium. See Major Die Break.
Rim — A die break restricted to the rim area of the coin. The raised portion of the border between the coin field and outside edge of the coin.
Rotated Reverse — This occurs when the reverse and the obverse dies are not correctly aligned prior to the striking of coins. See the chapter on rotated reverses.
Scratch — Deep line or groove in the surface of a coin caused by contact with a sharp object.
Strike — The process of forming or stamping the design of a coin onto a planchet. Also refers to the strength or sharpness of the detail of the design impressed into the coin.
Toning (Tarnish) — Natural discoloration of a coin caused by exposure to the environment.
Tripled Die — The tripling of the features on a coin via the hubbing process. See Doubled Die Obverse or Doubled Die Reverse.
Uncirculated — A coin that has not circulated and shows no visible signs of wear. May be brilliant or toned.
Variety — Any coin that is recognizably different from another of the same design, date and type. Generally applied to variations that are considered “collectible.”
This “Goatee” variety is found on the 2005-P Oregon 25c. These minor varieties can bring you $2.00–$5.00
Weak Strike — A weakness in the design features caused from too little pressure during striking. Often erroneously used to describe a coin struck from a worn die with mushy or weak details.
Working Die — A finished die used to produce coins, versus a Master die used to create hubs.
Working Hub — A hub created from a master die, used to produce working dies.