Post 2

These coins were much smaller than dimes in diameter and thickness, appearing to be "half dimes". In the 1860s, powerful nickelinterests successfully lobbied for the creation of new coins, which would be made of a copper-nickel alloy; production of such coins began in 1865, and were struck in two denominations — three and five cents (the latter introduced in 1866).

1. The introduction of the copper-nickel five-cent pieces made the silver coins of the same denomination redundant, and they were discontinued in 1873.

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He half dime, or half disme, was a silver coin, valued at five cents, formerly minted in the United States.

Some numismatists consider the denomination to be the first coin minted by the United States Mint under the Coinage Act of 1792, with production beginning on or about July 1792. 

However, others consider the 1792 half disme to be nothing more than a pattern coin, or 'test piece', and this matter continues to be subject to debate.