Glossary of Coin Collecting

A – C

Album – A book or binder with slots for holding coins in a series.

Alloy – A mixture of two or more metals. For example, U.S. “clad” coins are made of copper and nickel.

Authentication – The process of verifying that a coin is genuine.

Bag Mark – Small nicks or scratches caused when coins collide in mint bags.

Bullion Coin – A coin struck primarily for its precious metal content (gold, silver, platinum). Examples: American Silver Eagle, American Gold Eagle.

Cameo – A proof coin with frosted designs that contrast with mirrored backgrounds.

Clad Coinage – Modern coins composed of layers of copper and nickel, introduced in 1965.

Counterfeit – A fake coin intended to deceive collectors or circulate as genuine.

D – F

Die – A hardened piece of metal engraved with a design used to strike coins.

Die Crack – A raised line on a coin caused by a cracked die.

Double Die – A variety caused when a coin die receives a misaligned impression, resulting in doubled details.

Edge – The outer border of a coin, which may be plain, reeded (grooved), or lettered.

Encapsulated – A coin sealed in a protective plastic holder by a third-party grading service.

Error Coin – A coin with a mistake from the minting process, such as off-centering or missing design elements.

Face Value – The legal monetary value stamped on a coin (e.g., a quarter is worth 25 cents).

G – L

Grade – A measure of a coin’s condition and quality, typically on the Sheldon scale from 1–70.

Hairlines – Fine scratches, often from cleaning, that reduce a coin’s grade.

Hub – A master tool used to create dies for striking coins.

Intrinsic Value – The market value of the metal in a coin, separate from its face or collector value.

Legal Tender – Currency that must be accepted for debts, such as U.S. coins and paper money.

Liberty – The allegorical figure representing freedom, featured on many U.S. coins.

M – O

Melt Value – The value of a coin based on its precious metal content.

Mint – A facility where coins are produced. The U.S. Mint operates locations in Philadelphia, Denver, San Francisco, and West Point.

Mint Mark – A letter on a coin identifying the mint where it was struck (e.g., “P” for Philadelphia, “D” for Denver).

MS (Mint State) – A coin that shows no wear; synonymous with uncirculated.

Numismatics – The study and collection of coins, tokens, medals, and paper money.

Obverse – The “front” side of a coin, usually featuring the main portrait or design.

P – S

Patina – Natural toning or surface change that develops over time, often seen on copper coins.

Planchet – A blank metal disk prepared for striking into a coin.

Proof – A specially struck coin with sharp details and polished surfaces, often for collectors.

Reverse – The “back” side of a coin, usually featuring a complementary design to the obverse.

Rim – The raised edge around the outside of a coin.

Series – All coins of a particular design and denomination (e.g., Lincoln Cents).

Slab – Collector slang for a coin graded and sealed in a plastic holder by a grading service.

Spotting – Discoloration or dark spots that can appear on coin surfaces, especially silver.

T – Z

Token – A privately issued piece resembling a coin, often used in trade or transportation.

Toning – Color changes on a coin’s surface due to environmental exposure. Can be natural or artificial.

Type Set – A collection with one example of each major coin design, rather than every date and mint mark.

Variety – A coin with a small design difference from the standard issue, often due to a die change.

Wear – Loss of detail on a coin due to circulation.

Whizzing – An artificial cleaning process using a wire brush or wheel, often to make a coin appear uncirculated.