Numismatic Glossary
A handy reference guide for common coin collecting terminology, acronyms, and industry lingo.
About Uncirculated (AU)
A grading designation for a coin that has slight wear on the highest points of the design, typically retaining most of its original mint luster.
Auction
A public sale where coins are sold to the highest bidder, commonly used by major numismatic houses to price rare and high-end specimens.
Authentication
The process of verifying whether a coin is genuine and not a counterfeit, modern copy, or altered piece.
Bag Marks
Surface scratches, abrasions, or nicks acquired by uncirculated coins when they rub against one another in mint bags during storage or transport.
Bullion
Precious metals (gold, silver, platinum, palladium) valued strictly by their weight and purity rather than numismatic rarity.
Business Strike
A coin produced specifically for everyday commercial circulation and general commerce rather than for collector sets.
Bust
The upper body portrait of a person, figure, or allegorical character (like Liberty) featured on a coin's design.
Circulated
A coin that has been spent in daily commerce and shows varying degrees of wear, friction, and handling marks.
Clad Coin
A modern coin made of multiple bonded layers of different metals (such as a copper core wrapped in copper-nickel), common in post-1965 U.S. coinage.
Coin Album
A book-style holder with transparent sliding windows designed to securely display and organize a collection of coins by date and mint mark.
Coin Capsule
A hard, clear, two-piece snap-together plastic container used to protect individual coins from environmental exposure and physical damage.
Coin Dealer
A professional merchant or business that buys, sells, appraises, and trades coins and precious metals.
Coin Flip
A transparent plastic or paper-and-plastic pocket used to store individual coins, often sealed with a staple or heat press.
Coin Folder
A folding cardboard holder with circular cutouts where coins can be pressed in for viewing, though they typically expose one side of the coin to the air.
Coin Show
A gathering or convention where numismatists, dealers, and collectors buy, sell, and exhibit coins and currency.
Commemorative Coin
A special coin issued by a government to honor a notable person, event, anniversary, or landmark, often in limited quantities.
Common Date
A year and mint mark combination within a coin series that was produced in large quantities and is easy to find today.
Composition
The metallic makeup or alloy elements that a coin is manufactured from (e.g., 90% silver and 10% copper).
Counterfeit
An unauthorized fake coin manufactured with the deliberate intent to deceive buyers or collectors into thinking it is genuine.
Copper-Nickel
An alloy commonly used for modern circulating coins, typically consisting of roughly 75% copper and 25% nickel.
Date
The year inscribed on a coin, representing either the year of production or the year authorized.
Denomination
The official face value assigned to a coin by the issuing authority (e.g., one cent, ten cents, one dollar).
Details Grade
A designation given by professional grading services to a coin that is genuine but has physical problems like cleaning, scratches, or damage, meaning it cannot receive a numerical grade.
Device
Any principal design element on a coin, such as a portrait, symbol, eagle, or primary emblem, raised above the field.
Die
A hardened piece of steel engraved with the mirror-image of a coin's design, used to stamp blank planchets.
Dime
A United States coin with a face value of ten cents.
Dollar Coin
A coin with a face value of one dollar, historically minted in silver or large base metals, and later in smaller modern compositions.
Double Die
A major mint error caused when the hub strikes a coin die multiple times out of alignment, resulting in doubled details on the finished coins.
Edge
The outermost border surface of a coin connecting the obverse and reverse, which can be plain, reeded, lettered, or ornamented.
Error
A mistake made during the manufacturing process at the mint, resulting in a defective or unusual coin.
Eye Appeal
The overall visual attractiveness of a coin, taking into account luster, toning, blemishes, and overall aesthetic beauty.
Face Value
The legal monetary value printed or stamped on a coin by the issuing government.
Field
The flat, background surface of a coin surrounding the main design devices and lettering.
Grade
A numerical or descriptive rating (typically on the 1-70 Sheldon Scale) indicating a coin's condition, wear, and state of preservation.
Grading
The professional or personal evaluation process of assessing a coin's preservation state and wear level.
Hairlines
Fine, microscopic scratches on a coin's surface, often caused by improper cleaning, wiping, or harsh handling.
Half Dollar
A United States coin with a face value of fifty cents.
Key Date
A scarce year and mint mark combination in a coin series with a low mintage, making it rare, highly sought-after, and expensive.
Legend
The primary inscriptions or lettering running around the outer periphery of a coin.
Low Mintage
A very small total quantity of a specific coin produced by a mint during a given year.
Luster
The frosty, reflective shine or cartwheel effect produced by light bouncing off the microscopic flow lines of an uncirculated coin.
Medal
A metallic object struck to commemorate a person, event, or award, which functions as a piece of art rather than official government currency.
Melt Value
The intrinsic base market value of the raw precious metals contained within a coin.
Microscopic (Mint Error)
Unusual or unique variations produced during the minting process due to malfunctioning dies, planchets, or presses.
Mint (Facility)
An official government manufacturing plant authorized to produce coins for circulation or collection.
Mint Mark
A tiny letter stamped onto a coin designating which branch mint facility manufactured it.
Mint Set
An official pack or set of uncirculated business-strike coins issued by a national mint for collectors in a given year.
Mint State (MS)
The grading category for uncirculated coins spanning from MS-60 to MS-70, showing absolute zero wear from circulation.
Mintage
The total number of units of a specific coin produced by a mint.
Nickel
A five-cent United States coin composed primarily of copper and nickel.
Numismatics
The scientific study, collection, and history of coins, tokens, paper currency, and related monetary items.
Numismatist
A person who studies, collects, deals in, or researches numismatics.
Obverse
The front side or 'heads' of a coin, typically featuring the main portrait, date, and primary issuing text.
Original Surfaces
A coin whose surfaces have never been chemically altered, cleaned, polished, or tampered with since it was minted.
Patina
A natural tarnish, oxidation film, or artistic color development that coats a coin's surface over decades of exposure to air.
Penny
The common colloquial term for a one-cent coin.
Planchet
The blank, flat disk of metal before it is fed into a press to be struck into a finished coin.
Plain Edge
An outer coin rim that is completely smooth, lacking any grooves, reeding, or lettering.
Portrait
A realistic or artistic facial rendering of a historical figure or leader depicted on a coin.
Proof
A specially produced collector coin struck multiple times using highly polished dies and blanks to create mirror-like fields.
Proof Set
An official annual collection of proof-quality coins packaged directly by the mint for collectors.
PVC Damage
Corrosion, green slimy film, or pitting on a coin caused by chemical plasticizers leaching out of older vinyl storage flips.
Quarter
A United States coin with a face value of twenty-five cents.
Reeding
The series of small vertical grooves or ridges stamped along the outer edge of a coin.
Registry Set
A competitive online system where collectors register their certified slabbed coin collections to rank them against peers based on grade and completeness.
Relief
The portion of a coin's design that stands out or is raised higher than the flat background field.
Reverse
The back side or 'tails' of a coin, opposite the obverse.
Rim
The raised border running along the outer perimeter of both sides of a coin, designed to protect the design from wear.
Semi-Key Date
A coin issue that is moderately scarce and more valuable than common dates, though not as rare or expensive as a true key date.
Sheldon Grading Scale
The universal 1-70 numerical scale used by numismatists and grading services to grade the condition of coins.
Silver
A precious white metal widely used historically for worldwide coinage due to its intrinsic value and malleability.
Slab
A sonically sealed, tamper-evident hard plastic holder issued by third-party grading services to authenticate and grade a coin.
Spot Price
The current global market trading price for one troy ounce of a precious metal for immediate delivery.
Strike
The physical process of pressing a die into a metal planchet, or the sharpness and clarity with which the design was impressed.
Third-Party Grading (TPG)
An independent professional authentication and grading organization (such as PCGS or NGC) that encapsulates and grades coins.
Token
A privately issued piece of metal or composite material used in place of official government currency for specific goods or services.
Toning
Natural surface discoloration or chemical coloration caused by exposure to atmospheric elements over time.
Type Coin
A representative coin of a specific design series, denomination, or era used as an example of that style.
Type Set
A collection of coins gathered to feature one example of every major design style or denomination type across a country's history.
Uncirculated
A pristine coin that has never entered general circulation and retains its absolute original factory finish.
Variety
A minor variation or distinct deviation from the standard master die of a coin series, such as a repunched mint mark or unique lettering style.
Wear
The physical loss of metal and microscopic abrasion on a coin's high points caused by repeated handling and circulation.