Coin Terms O-Z

oddity – When something unusual happens to a coin it is sometimes called an oddity. Also known as error coins, or something that was done to a coin after the minting of the coin.

obsolete – A coin series or specific design that is no longer in production. Obsolete coins have a certain appeal as they will never be produced again adding to the rarity.

obverse - The front side of a coin, usually displaying the main design, date and sometimes mint mark. The back of the coin is called the reverse.

off center – Describes the incorrect way a coin was struck by the printing dies. Happens when the coin is not placed properly into the collar and the dies strike it off center. Portions of the design will be missing. Sometimes off-center coins have part of the blank planchet showing.

OGP – Original government packaging, used to hold US Mint and Proof sets.

O Mint – Located in New Orleans, Louisiana. Operated from 1838 until 1861 and agian from1879 until 1909.

original – Term used for an original coin that has never been cleaned are polished.

original roll – A group of coins that were wrapped in paper wrappers at the time of their production at the Mint. This method is used for maximum space needed to move billions of coins around the country. Rolled coins tend to have fewer marks than those stored or transported in bags.

over dipped – A coin that has lost it’s original luster from being dipped too many times.

over strike – A coin that instead of being struck on a blank planchet was accidentally struck on a previously struck coin. Example: a 2008 Guam design struck over a 2008 Arizona quarter. Categorized as an error coin.

PCGS – Professional Coin Grading Service, an independent third party coin grading and authentication service. One of the most trusted and respected in the industry.

pattern – A coin that was struck as an experiment or as a trial piece. Usually, a new design or made of experimental metal alloys. Still considered government property, resent U.S. Pattern coins  are illegal to own. Older patterns were given to VIP’s and are available to legally buy or sell in the numismatic market place.

pedigree – A kept list a coin’s current and previous owners. Pedigree can also refer to a coin’s history, benefits, highlights, etc.

planchet – A round piece of metal pressed from large sheets in which the coin is struck. Also called a blank.

P Mint – Located in Philadelphia, Pennsylvania. Began operations in 1793 and is still producing coins today.

population report – Reports posted by grading services that number quantities of each grade of certified coins by type of coin.

precious metal – Metals of value traded on the open markets. Typically gold, silver, platinum, palladium and rhodium.

Professional Coin Grading Service – See PCGS.

proof - Collectible coin produced from heavily polished dies and a polished planchet. Each proof coin is struck two or more times on each side which gives the coin an incredibly sharp frosted image that floats on a  mirror like background. Proofs are not made to circulate. Mishandling can lower the grade thus lowering the value of a proof coin. Proofs are sold by the Mint during their year of production at a premium to offset special production costs.

proof set – A group of all the different denominations of proof coins made for that year. Usually sold in original government packaging. Currently, all proof sets are made at the San Francisco Mint.

raw – Term describing a coin that has not been certified and sealed into a slab.

reeded edge – The far edge of a coin that has tiny reed like dots or lines on it. US dimes and quarters are today’s examples of reeded edge coins.

relief – The portion of the design that raises above the surface or field of a coin.

re-strike – A coin minted from genuine dies at a later date than the original issue.

reverse – The back side of the coin. Opposite the obverse side.

reverse cameo – Also known as reverse proof. A coin where the field is frosted and the design is mirrored. Essentially flipping the contrast of a proof coin.

riddler – The Mint’s machine that sorts out the incorrect size and defective blanks.

rim – The raised edge of a coin created by the upsetting mill and collar. The raised edges on both sides of a coin help protect the coin’s design from wear.

roll – A stack of coins of the same denomination in a paper wrapper package. This can be done by individuals, retail centers, banks or at the Mint. The coin denomination determines the number of coins in a roll.

rounds – One ounce coin shaped pieces of silver pressed from sheets of silver metal.

satin finish – See burnished die.

series – Collection of coins of one denomination that contains all the mint marks and dates available of that particular design. Example: a complete series of the State Quarters would consist of one of each quarter from the Denver, Philadelphia and San Francisco Mint issued between 1999 and 2008.

seigniorage – The difference between the cost of minting a coin and what the mint generates in money for it. It may only cost .10 to manufacture a half dollar. However, the mint gets 50 cents for it. The result is .40 seigniorage.

sight unseen – Coins purchased without prior visual inspection. Collectors feel more comfortable purchasing sight unseen when coins are certified and slabbed.

slab or slabbed – Slang for a holder holding a coin that has been encapsulated by a coin grading service. Usually, the coin will graded, authenticated, and encapsulated in a sonically sealed holder, often by a 3rd party grading service. See PNG, NCG, ANACS, PCGS.

slab – Term describing the hard plastic shatter-proof container that most grading services use to package a coin to keep from the elements. Slabbed coins are usually certified by the grading service and have been guaranteed genuine.

S Mint – Located in San Francisco, California. Began operations in 1854. Still producing coins today. They only produce proof coins.

strike – The process of using high a pressure press to stamp a design into a coin planchet.

spotting or spot – A mark or marks on a coin from liquids are residue from when they were cleaned at the mint. Usually, it is a form of tarnishing or staining. Spotting usually negatively effects the value of a coin. Do not try cleaning spots as this could cause damage.

tail - The Backside or reverse of a coin.

toning – Toning results when the surface of the coin comes in contact with the air and environment. Areas of the coin turn color. It can cover just a small portion of the coin or the entire thing. Some experts think toning makes a protective coating over the surface of a coin that helps the coin resist corrosion.

troy ounce - 1 troy ounce equals 31.1 grams.

truncation – The bottom edge of a coin where a portrait or bust has been sharply cut off.

two bits – See bits.

two cent piece – A US coin with the value of two cents. Example: the copper shield design made from 1864 to 1873.

type – Coins sharing the same characteristics. A type collection consists of one of each representative design. Example: there were 12 types of US circulated gold.  A type set would consist of one of each variety struck, does not need to be every mint mark and date.

type set - See type.

uncirculated – Or known as Unc, a new condition coin that does not have any sign of wear. Marks on the coin that may come from the manufacturing process do not keep a coin from being uncirculated. The slightest amount of circulation wear or cleaning will keep a coin from grading uncirculated.

upsetting mill – The Mint’s machine used in coin production to raise the rim on both sides of a blank.

varieties - Minor differences in a coin’s design. Sometimes varieties are error coins.

waffled – The process where the Mint destroys defective or worn coins by running them through a waffling machine giving them a waffle like appearance. Coins destroyed by this process can be sold in bulk for scrap metal and often cannot be distinguished as a US coin.

walker – Nick name for the Walking Liberty Half dollar struck from 1916 to 1947.

W Mint – Located in West Point, New York. Began operations in 1984. They produce the majority of our precious metal coins.