Terminology
A
AGW (Actual Gold Weight)
The amount of pure gold in a coin, measured in troy ounces.
ASW (Actual Silver Weight)
The amount of pure silver in a coin, measured in troy ounces.
Alloy
A mixture of metals used to create a coin.
Alteration
An illegally changed or tampered coin to increase value by making it appear higher grade or different than original.
ANA
Abbreviation for American Numismatics Association, established in 1891. Largest organization of coin collectors in the world.
Annealing
The process of heating metal to soften it for striking.
Authentication
Verification that a coin is genuine.
B
Bag Marks
Small scratches or nicks on a coin caused by contact with other coins during storage or transportation.
Base Metal
A non-precious metal (e.g., copper, nickel) used in coinage.
Bicentennial Coins
Coins issued to commemorate the 200th anniversary of an event.
Bit
An old Mexican coin (Value 12.5 cents) circulated in America during the 1800s.
Bitcoin
Bitcoin is a digital currency — also called cryptocurrency — that can be traded for goods or services with vendors that accept Bitcoin as payment. With Bitcoin, holders can buy, sell and exchange goods or services without a central authority or bank as an intermediary.
Blockchain
Blockchain is a digital ledger system, foundational to the world of cryptocurrency and beyond. It offers a decentralized, transparent, and secure method of recording transactions across multiple computers.
Body bag
Slang term for a coin returned from a grading service in a plastic sleeve within a flip. The coin referred to is deemed a "no-grade" and is not graded or encapsulated. Coins are no-grades for a number of reasons, including questionable authenticity, polishing, cleaning, and/or repair.
Brilliant Uncirculated (BU)
A coin that has not been circulated and retains its original mint luster.
Burnishing
A process in which the surfaces of a coin or a planchet are shined through rubbing or polishing. This term has both a positive and a negative context: In a positive sense, Proof planchets are burnished before they are struck. The procedure was done originally by rubbing wet sand across the surfaces to impart a mirror-like finish. In a negative sense, the surfaces on repaired or altered coins may be burnished by mechanical or chemical methods. For example, a high-speed drill with a wire brush attachment is used to achieve this effect.
C
Cameo
The contrast between a coin's raised design and its background. Shows frosted finish on raised design and mirror-like finish on background.
Cartwheel Effect
A reflective pattern of light on a coin caused by its mint luster.
Certified Coin
A coin authenticated, graded, and encapsulated by a professional grading service.
Clad Coinage
Coins made of layers of different metals, such as copper-nickel-clad coins.
D
Denomination
The face value of a coin (e.g., $1, 10¢).
Die
A metal disk engraved with the design and lettering for one side of the coin.
Die Crack
A raised line on a coin caused by a crack in the die.
Double Die
A manufacturing error where the design on a coin die is duplicated, resulting in doubled features on every coin struck.
E
Edge
The outer border of a coin, which may be plain, reeded, or inscribed.
Error Coin
A coin with a mistake in its design, planchet, or striking process.
F
Face Value
The nominal value printed on a coin.
Field
The flat area (background) part of a coin's surface not occupied by design elements.
Fineness
The purity of precious metal in a coin, expressed as a decimal.
G
Grade
The numerical or descriptive condition of a coin, ranging from Poor (P-1) to Perfect (MS-70).
Grading Service
A professional organization that evaluates and certifies a coin's condition (e.g., PCGS, NGC).
H
Hairlines
Thin scratches on a coin, often caused by cleaning or handling.
Hub
A master die used to create working dies.
I
Incuse
The areas of the coin design impressed below the surface (opposite of relief).
Intrinsic Value
The value of the metal content in a coin.
K
Key Date
A rare or highly sought-after date within a coin series.
L
Lamination
A flaw where a thin layer of metal separates from the coin's surface.
Legal Tender
Coins or currency officially recognized for the payment of debts.
Luster
The shine on the surface of an uncirculated coin.
M
Mint
A facility that produces coins.
Mint Mark
A small letter or symbol on a coin identifying the mint where it was struck.
Mint Luster
The original, shiny surface of a newly minted coin.
N
Numismatics
The study and collecting of coins, paper money, and medals.
Numismatist
A person who studies or collects coins and related items.
O
Obverse
The front side of a coin, typically displaying a portrait or primary design.
P
Patina
A natural or artificial discoloration or toning on a coin's surface.
Planchet
A blank metal disc prepared for striking into a coin.
Proof
A specially made coin with high detail and a mirror-like finish, intended for collectors.
R
Reeded Edge
A series of grooves on the edge of a coin, often used to deter counterfeiting.
Reverse
The back side of a coin, opposite the obverse.
S
Series
A complete set of coins of a particular design and denomination.
Strike
The process of impressing a design onto a planchet to create a coin.
T
Toning
A natural coloration on a coin caused by exposure to air or chemicals over time.
Type Set
A collection of coins with one example of each design type.
U
Uncirculated
A coin that has not been used in commerce and retains its original condition.
V
Variety
A coin that differs slightly in design or details from others of the same type and year.
W
Wear
The erosion of a coin's surface from use or handling.
Whizzed
An artificial process whereby the surface of a coin is buffed to give it the appearance of having natural cartwheel lustre.