There are currently 16 names in this directory beginning with the letter O.
Obsolete Banknotes
Banknotes issued by banks under permission of the Department of the Treasury that were supposed to be backed by the assets of the issuing bank. The National Bank Act of 1863 made these banknotes obsolete.
off metal
A type of error that occurs when a coin is struck on a planchet that it is not normally struck, such as striking of a quarter on a planchet that was supposed to be for a nickel.
omitted design
These errors are the result of elements missing from the master dies when working does were created. Missing elements can include omitted dates, mintmarks, legends, or parts of the design not included on the master die.
open collar
A device used to position a planchet over the lower die. It was employed specifically for striking early U.S. coins whose edges had already been stamped with reeding or lettering.
original
Referring to any aspect of a coin that retains its original state. Original toning means natural, not retoned or cleaned. Original luster means undisturbed luster that has not been enhanced through artificial methods.
original surface
Term used to describe a coin that has never been altered. It is the original surface of the coin as it was when it was released from the mint.
over-grading
The practice of assigning a coin’s grade a value above what it truly deserves. An inexperienced grader or a deliberate act to deceive buyers can be reasons coins may be over-graded. See also grade.
overstrike
A type of minting error when a coin, token or medal is struck on a previously struck coin, token or medal.
oxidation
The formation of oxides or tarnish on the surface of a coin, token or medal from exposure to the environment. See also toning.