Alloy
A mixture of more than one metal.
Authentication
An authoritative determination of a coin’s genuineness.
Blank
A piece of coin-shaped metal that is stamped to be made into a coin.
Burnishing
A form of surface preparation on proof or uncirculated blanks, using steel balls and detergent to remove any unwanted watermarks from the surface of the blank.
Circulating coin
A coin that has been issued by a bank.
Coin
Usually a piece of metal marked with a device, issued by a government authority, and intended to be used as money.
Denomination
The stated face value of a coin.
Die
A hardened metal tool, the face of which carries an engraved design that is to be stamped onto a blank.
Effigy
A sculpted image of a person, usually a monarch, to appear on the obverse of a coin.
Frosting
An effect in which parts of a coin are slightly dulled (using sandblasting techniques) to provide a contrast to the shinier parts of metal.
Grade
A carefully constructed series of guidelines to determine the condition and therefore the rarity and value of a coin.
Mint mark
A letter or symbol, indicating the mint of origin.
Mule
A coin, token or medal whose obverse design is not matched with its reverse.
Numismatics
The science, study or collecting of coins or similar objects.
Numismatist
A collector or knowledgeable person in the field of numismatics.
Obverse
The ‘heads’ side of a coin, usually carrying the effigy of the ruling monarch.
Pickling
A process in which proof blanks are cleaned in acid to remove oil, directional rolling lines and dirt from their surface.
Plaster
A model made during the design process, to help refine the image and its details.
Proof coin
A coin struck carefully using special dies, with frosted images on a mirror-like background. Proof is a method of manufacture, not a condition or grade.
Reverse
The ‘tails’ side of a coin, carrying a design to distinguish coins from one another.
Rim
A raised area of metal around the edge of a coin. It is intended to protect the rest of the coin from wear.
Uncirculated coin
A coin which has not been distributed or used as currency.
Uniface
A coin, medal or token which has only been struck on one side.