ALLOY     The fixed proportion of metals in a coin.  Mixture of metals.  Roosevelt  dimes produced from 1946 until 1964 are a metal alloy composed of 90% silver and 10% copper.


ANNEAL     Soften metal by heating.  Die blanks are annealed  before engraving and during the hubbing process.  Coin planchets are annealed before striking to help extend the life of dies.





BLANK     An unstruck planchet.


BORDER     Raised circle whose outer edge is the rim.  Area between the field and the edge of the coin.


BUSINESS STRIKE     One blow from the dies.  A coin struck with the intention of normal circulation or commercial use.  Working die life according to Mint Bureau statistics for the Roosevelt dime are 150,000 obverse strikes and 165,000 reverse strikes.





CHATTER     Unwanted vibration of a die which produces minor doubling, tripling, etc. on the design elements of a coin.


CHERRYPICK     To recognize and purchase a rare coin, variety, or error which has been offered for sale a common item.


CLASH MARKS     The impression of a die which has been left in the die that faces it in a press.  This is caused when the dies strike each other during the coining process when there is no planchet between them.



CUD     A lump of metal found on a coin which has been struck with a die from which a portion has broken off.





DEVICE     A principal design element.


DIE     The item which stamps a design into a blank planchet.


DIE CRACKS     Raised lines which appear on a coin as the result of having been struck by a cracked die.


DIE STATE     Distinct state in the life of a die.  The die state will vary from new to unusable and may include different states of disrepair such as cracked, chipped, rusted, broken, etc.  During the life of a die, the appearance of a crack or a clash mark will represent a specific die state.


DIME     Official and legal name for the coin representing 10 cents or 1/10 of a dollar.


DOUBLE STRUCK     Term referring to any coin which has received two impressions form working dies which were accidentally out of alignment during the coining process.


DOUBLED DIE     A die which has received one of its impressions from a hub or punch which was accidentally misaligned  during use.  There are a number of different causes for this misalignment.





EDGE     Outside surface of a coin which may be reeded, lettered, flat, or with some type of design.  The Roosevelt dime has a reeded edge.  Often called the third side of a coin.





FIELD     The plain background around the devices on a coin or die.





GALVANO     The impression of a plaster model of a coin made by electro-deposition.  One of the early stages in the development of master dies used for coins or medals.





HUB     A special die used to press the image of a coin into a working die.  Several blows from the hub are necessary to impress an image into a working die.  Hubs are not used for striking coins.





INCUSE     Those parts of a coins design that are below the field.  Opposite of relief.


INSCRIPTION     Words and numerals on a coin.  Inscriptions do not include dates, mintmarks, or designers initials.





JANVIER REDUCING MACHINE     A type of lathe used for making reduced-size copies of the galvano in the production of master dies.





LEGEND     That portion of a coin inscription which is placed in a semicircular arc next to the border of a coin.








MASTER DIE     An original die made from the master hub.  This die is used for making working hubs.  It is not used for striking coins.


MASTER HUB     The original hub made by the Janvier reducing machine from the galvano or model of the coin to be produced.


MINT     (1)  Establishment which produces coins.  (2)  To strike coins.


MINTAGE     Quantity of coins struck.


MINTMARK, MINT MARK     A letter or other symbol representing the mint which produced a coin.  Mintmarks are usually hand punched into working dies.


MOTTO     A phrase found on the surface of a coin.  The phrases IN GOD WE TRUST and E PLURIBUS UNUM are examples.





NUMISMATIST     Word preceding NUMSKULL in the dictionary and refers to a person who knows much about the study of coins and medals.





OBVERSE     The front or "heads" side of a coin.


OVERMINTMARK, OVER MINTMARK, OVER MINT MARK     Variety in which the letter designation for one mint is punched over the letter designation for another mint on a working die.





PLANCHET     The metal on which a design is struck to produce a coin.


PRESS     The machine which supplies the striking force or pressure to produce coins or hubs and dies.


PRODUCTION COIN     Same as a business strike coin.  Coin meant for circulation/commerce.


PROOF     A coin which has been made with special care and special procedure.  Proof coins are struck almost exclusively for collectors.  They are almost always struck twice with specially prepared dies.  The details on proof coins are usually much sharper than on business strikes.  Proof die life according to Mint Bureau statistics for the Roosevelt dime are 2,600 obverse strikes and 2,700 reverse strikes.


PUNCH     Instrument used to impress (punch) a design feature into a die.


PUP     Pick up point.  The area on a coin by which a given variety can be identified.





REEDING, REEDED EDGE     The vertical ribs or lines on the outside edge of a coin.


RELIEF     Those parts of a coin design which protrude above the field.  Opposite of incuse.


REVERSE     The back or "tails" side of a coin.


RIM     That portion of a coin where the border meets the edge.





SAN-SERIF     Description of letters without serifs.


SHELDON SCALE     Developed by Dr. William Sheldon, the numerical system for grading large cents which was adapted for use with all coins in the 1970's.  The system incorporates the numerical grades of 1 through


70 to correspond with the accepted descriptive grades as follows:


     Poor - 1

     Fair  - 2

     Almost Good - 3

     Good - 4, 6 

     Very Good - 8, 10

     Fine - 12, 15

     Very Fine - 20, 30

     Extremely Fine - 40, 45

     Almost Uncirculated - 50, 55

     Mint State - 60, 63, 65, 67, 70


     Current practice allows intermediate grades such as Very Fine-25 or Mint State-62 to be used.


STRIKE     (1)  To stamp a design into a blank planchet.  (2)  The degree of detail a coin had when first struck.  Dependent on die state, this detail may vary from shallow and weak to bold and sharp.





TROY OUNCE     Weight which is equal to !/12 troy pound =

                                                                        480 grains =

                                                                         31.1 grams.


TYPE     Change in the design of a coin.  The "near Y" and "Far Y" types of 1946 Roosevelt dimes are examples.





VARIETY     A coin which is recognized as different in detail from other coins of the same type, year, mint, et cetera.








WORKING DIE     The die used for striking coins.


WORKING HUB     The hub used for making working dies.