Obverse

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

Overdate

Up until the early 20th century, most U.S. coins had dates hand-punched directly into working dies. An overdate is simply the result of a new date being punched into a die over an old date by punching one or more numerals individually, or using a gang punch to punch an entire date over the old. During the early part of the 20th century, dates were included as part of the hub removing the need to punch the date into each die. However, overdates could also occur after the date became part of the hub. This occurred when a wrong dated hub was used to impress the coin design into a die and then a correct dated hub was impressed on top of that. Overdate coins are usually identified by dates written similar to the following example: 1853/4 where the numeral 4 has been superimposed over the numeral 3.

See also - - Gang Punch, Hub, Repunched Date

Over Mintmark (OMM)

Up until the late 20th century, U.S. coins had mintmarks hand-punched directly into working dies. An over mintmark is simply the result of one mintmark being superimposed over another mintmark in the die. Examples of this are frequently found in with Morgan dollars such as O over CC. In 1985, the mintmark was added to the hub for proof coinage. In 1990, the mintmark was added to the hub for circulating coinage.

See also - - Hub, Over Mintmark