Minting and Coin Terminology
Ag - elemental abbreviation for Silver.
Alloy - a mixture of two or more metals melted into one compound.
Anvil Die - this is the bottom die. A coin is struck using two dies. One for the obverse
(front) of the coin and another for the reverse (back). The anvil die is the one on the
bottom, which is usually the reverse. The term comes from when the die was placed on
an anvil with the coin blank (planchet) on top. The hammer die (top die) was placed on
top of the coin and struck with a hammer.
Annealing - the process of heating coin blanks (planchet) in a furnace to soften the
metal prior to striking coins out of them.
Assay - To test a metal for purity.
Au - elemental (scientific) abbreviation for the metal GOLD.
Blank - a blank piece of metal on which a coin design can be stamped. Also called a
planchet. Usually already cut into the shape of a coin - but without any design.
Cast Coin - a coin that was made by pouring melted metal into a mold or cast. Not
made by striking a die against a blank like most coins. Casting was a common
process used to try to counterfeit coins.
Collar - when a coin is struck the collar on the printing press surrounds the rim of the
coin preventing the metal from flowing outside of the collar.
Commemorative - a special coin or medal issued to honor an outstanding person,
place, or event. Often one time or short lived production. Many times commemorative
coins are not produced for general circulation.
Designer - an artist who creates the design. Not the engraver (who actually makes the
coin producing dies). Although, in years past some designers were also engravers.
Die - an engraved metal stamp used for stamping out the design of a coin. The die is
often hardened so that when it strikes the metal blank an impression will be left
indicating the coins design, value, and wording.
Die defect - refers to damage or defect of a coin die. The coins produced by that die
will exhibit the same defects.
Edge - The "third side" of the coin that may be plain, milled or ornamented
Engraver - refers to an artist who creates a coin’s design as a model or sculpture. In
earlier days the engraver would actually cut out the design onto the die.
Field - The area of the coin with no design or inscription
Fineness - the purity of a coin, medal, or precious metal item. Uses a scale of 0 to
1.000. Examples: A silver coin with a fineness of .999 would be as pure as a coin can
be. A silver coin with a fineness of .500 would be made of 50% silver. Most 1964 and
earlier US (US Mint) silver coins were .900 fine, or 90% pure silver.
Frosted proof - this is a proof coin that has a mirror like surface in the background with
a frosted (or dull) surface on the design.
Grade - A rating that indicates the amount of wear and preservation of the coin
Hub - this is the coin production term used to refer to a reverse design that is used to
make the dies that strike the coins. Sometimes a punch that is used to stamp the
design into the coin die.
Hammer die - this is the top die. The hammer die is the top die that is placed on top of
the coin blank and struck. Years ago this was done with a hammer.
Inscription - pertains to the words stamped or written on a coin.
Legend - this is the main lettering on a coin. For example, the phrase “United States of
America.”
Medal - refers to an object made of metal that resembles a coin. Often medals are
made or given to recognize a person, place, or occasion. Medals have no stated value
and are not intended to circulate as money. Sometimes a medal may have intrinsic
value as in bullion value.
Mintage - The total number of coins produced for a specific program.
Mintmark - Small letters on the coin (e.g. MH) that identifies where the coin was struck
Numismatics - The study or collection of coins, tokens, paper money and medals.
Obverse - The "heads" side of the coin, usually with an effigy of the head of state or a
coat of arms
Ounce - a form of measuring weight. The troy ounce that is used for weighing precious
metals is different from the regular grocery store ounce.
Precious metal - These are metals of value. Typically gold, silver and platinum,
however they can include palladium and rhodium.
Proof - These are coins produced from polished dies and/or planchet. Typically, each
proof coin is struck twice/or more which gives the coin a very sharp degree of detail and
mirror like surface. Proof coins are usually made for numismatic purposes,
resentations, or souvenirs. Proofs are usually not made to be circulated in commerce.
Mis-handling can lower the value and grade of a proof coin. Proofs are sold by the mint
during their year of production at a premium to cover their special manufacturing costs.
Often, they are only sold in sets.
Proof-like - Not double struck and have rounded edges. Finish not as sharp as PRF
coins
Relief - This is the part of the design that is raised from the surface of the coin. An
example of this would be Washington’s face on a Washington quarter.
Reverse - The back or "tails" side of the coin, usually depicting the theme or event.
Sterling Silver - silver which is 92.5% silver and 7.5% Nickel. The Nickel makes the
metal hard enough to fashion jewelery and plate-ware from.
Strike - The process of stamping a coin blank with a design
Surface - the entire area of the coin, although often refers to field areas only
Toning - Refers to the shading of color on coins. Toning can be in many forms from
dark or brown to various shades of other colors. It can cover the whole coin or more
often part of the coin. Toning results when the surface of the coin comes in contact with
the air and environment it is exposed to. Traces of material in the metals will also play
a roll in the toning. Some people think toning makes a “protective” coating over the
surface of a coin that helps the coins resist corrosion. Toning can be even artificially
done by exposing the coin to certain reactive substances. Some “naturally” occurring
toned coins bring a premium in the collector market due to their unique beauty. Others
may bring less than an untoned coin when the toning is unattractive.
Troy ounce - a way to measure weight. A troy ounce differs from a regular “grocery
store.” The word ounce when applied to gold and silver always refers to troy ounces.
Type - A variation in design, size or composition of a specific coin design
