What this coin looks like (obverse, reverse, mint mark location, special features, etc.):
1804 is one of the rarest and most valuable years for the Draped Bust Large Cent (Penny) series. There are many fakes out there. The real ones will always have a crosslet "4" in the 1804 date. The crosslet is a vertical slash through the right-side end of the "4". There are also "restrike" varieties of this coin which were produced years later and do not have the crosslet "4". These restrikes will also have severe cracks due to cracked dies. Source of example image above is courtesy of Heritage Auction Galleries.
Coin valuation chart: Typical coin prices, values and worth per grade or condition - in USD