The United States began issuing Small Cents in 1857 for two reasons: first, because the cost of making the larger size Half-Cent and Large Cent had risen to the point where making the coins cost more than they were worth; and second, to encourage citizens to move away from using Spanish and English coinage (which had denominations such reals and shillings) and begin using an entirely U.S. issued decimal coinage.
Flying Eagle Cent - The first Small Cent, the Flying Eagle Cent, was issued as a pattern type in very small numbers in 1856, and business strike coins began in 1857. The Flying Eagle Cent didn't last long, though, with 1858 being its final year of issue. Specimens in G-4 grade of the 1857 and 1858 are worth about $10 if you want to sell them today.
Indian Head Cent - The so-called Indian Head Penny (which is actually a depiction of Lady Liberty wearing a feathered headdress) is a very popular type today. It replaced the Flying Eagle Cent in 1859 and was issued until 1909. An Indian Head Cent in G-4 condition will bring at least a dollar if you want to sell it; you can find a full breakdown of values in this table of Indian Head Penny values.
Wheat Ears Cent - The Wheat Ears Penny, also known as a feather back or wheat back penny replaced the Indian Head pennies in 1909, and continued until 1958. Wheat Pennies are always worth at least 4 cents if you can read the date; the copper bullion value in them alone is worth well over 3 cents a coin now. You can look up your wheaties in this full table of Wheat Penny values.
Lincoln Memorial Cent - The final issue of U.S. Small Cents is the Lincoln Memorial Cent, which began circulation in 1959, and continues until now. All Lincoln Memorial Cents prior to 1982 are worth at least 3 cents (for the copper bullion in them), and business strike cents after 1982 must be in fairly high grade (MS-60 or better), or be a variety type, to be worth more than face value. This table of Lincoln Memorial Cent values provides more information. For pennies dated 1982, you need to determine whether they are primarily copper or zinc in order to ascertain their value.
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