Canceled denominations of United States currency

The United States has several coins and banknotes which were proposed at one time but never adopted.

Banknotes
A three dollar bill was proposed two times during the 1860s. A design was engraved for a potential $3 United States Note, and a 1865 law called for a $3 National Bank Note, but neither proposal came to fruition.

Coinage
There have been several United States coins which were proposed but never adopted. Most of the coins listed below, although never adopted, were produced in limited numbers as patterns.