The half cent is the smallest denomination of United States coin ever minted. It was first minted in 1793 and last minted in 1857. During its existence, it was minted with five different designs.
First authorised by the Coinage Act of 1792 on April 2, 1792, the half-cent piece was made of 100% copper and was valued at five milles, or one two-hundredth of a dollar. It was slightly smaller than a modern U.S. quarter with diameters 22 mm (1793), 23.5 mm (1794-1836) and 23 mm (1840-1857).
The first design, known as the Liberty Cap, was issued from 1793 until 1797. Production of the half cent was temporarily suspended in 1797, then resumed in 1800 with the Draped Bust obverse, which had already been in use on the silver coinage for several years. These half cents were only issued until 1808 though, after which time this "Classic Head" design was introduced.
The Classic Head interpretation of Liberty was designed by John Reich for use on the half cent and the large cent; however, the design used on the silver and gold coins was developed by William Kneass. The Classic Head depicts Liberty with long, curly hair. The reverse, designed by John Reich, shows the coin's denomination and value inside a wreath. Beginning in 1831, new equipment at the mint and modified dies produced a raised rim on both sides of the coins.
This type of half cents was issued until 1836, then in 1840 the final "Braided Hair" design was introduced instead. As with all other half cent types, the coins were produced exclusively by the Philadelphia Mint.
The denomination was discontinued by the Coinage Act of February 21, 1857. While withdrawn from circulation and not used any more, the coins were never officially demonetised though.