Over mintmark

over mintmark
A coin struck with a die on which one mintmark is engraved over a different mintmark.

Over Mintmark - Similar to an Overdate, however, the mintmark is stamped twice into the coin (d/d) or another mints hub was passed along creating an over mintmark with two mint marks. Example 1900 O/CC.

Over Mintmark
This is similar to an Overdate except that the mint mark is stamped twice into the coin (d/d). Another possibility is one mint using another mint's hub which created an over mint mark with two different mint marks.

over mintmark
A mintmark punched on top of another mintmark, such as a 'D' over an 'S'.
overstrike
An impression made with different dies on a previously struck coin.

An over mintmark, similar to an overdate, is one mintmark punched over a different mintmark. The 1950-S/D Washington quarter is a good example. Values can reach several hundred dollars for an otherwise common 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.
P
PLANCHET The metal on which a design is struck to produce a coin.

Definition: An overpunched mintmark (OPM, or OMM for over mintmark) is a coin specimen that exhibits more than one different mintmark, one punched on top of the other.

You will notice that most RPMs (repunched mintmarks) and OMMs (over mintmarks) are identified simply, such as 1938-D/S 5c, OMM #1.

environmental conditions; uncleaned overdate A coin struck from a die with at least one digit of the date repunched over a different digit, e.g. 1809/6 or 1942/1. overgraded Designated with a higher grade than merited over mintmark One ...

OMM Over MintMark. Two different mintmarks involved. (versus RPM, which is the same mintmark punched more than once). Type of die variety. OT Off Topic. Internet phrase. OTOH On The Other Hand. Internet phrase.

See also: Mintmark, Coin, Proof, Collector, Marks