Post-reform coinage like the half crown you are mentioning are pretty common and so its unlikely to be faked. If you are concerned about it being fake, weigh it. It should weigh about 14.1 grams.
No, there is no silver in a 1817 US penny.
George A. Smith was born in 1817.
George Tattersall was born in 1817.
George Jenkinson was born in 1817.
George Thacher was born in 1817.
George Abert was born in 1817.
George Baigent was born in 1817.
George Wilkes was born in 1817.
George Flett was born on 1817-02-10.
George Ashley Maude was born in 1817.
George Ponsonby died on 1817-07-08.
George Robert Barker was born in 1817.