What Is A Key Date?

In coin collecting, a key date refers to a date (date and/ or mint mark combination) of a given coin series or set that is harder to obtain than other dates in the series. The next level of difficulty to obtain coins in a series are often known as semi-key dates or semi-keys.

Here is a list of some Key Dates for various denominations 

 Pennies (Key Date)

• 1793 Chain Cent- The Chain cent was America's first large cent and the first coin officially produced by the United States Mint.
• 1799 Draped Bust Cent- Our best guess is that only about 35,000 cents dated 1799 were struck, with no more than 1,000 surviving today.  
• 1804 Draped Bust Cent- 1804 is one of the rarest and most valuable years for the Draped Bust Large Cent series. Only were 96,500 minted.
• 1823 Coronet Large Cent- Mintage is not known on this coin, in average condition, this coin is worth $146.
• 1856 Flying Eagle Cent- 1856 was the first year that the US Small Cent was produced. Only 2,000 coins were minted during this year. in average condition, this coin cost  $7,788 dollars.
• 1877 Indian Head Cent- Only 852,500 were minted, in average condition, this coin costs $1,122.
• 1909-S Indian Head Cent- Just like the 1909 s vdb penny, this coin has a low mintage. only 309,000 were minted. In average condition, this coin is worth $602. 
• 1909-S VDB Lincoln Cent- Only 484,000 were minted, in average condition, this coin is worth $860.
• 1909-S Lincoln Cent- Only 1,825,000 were minted, in average condition, this coin is worth $110.
• 1914-D Lincoln Cent- Only 1,193,000 were minted, in average condition, this coin is worth $261 dollars.
• 1922 Plain Lincoln Cent- All 1922 Lincoln Wheat Cents (Pennies) were minted at the Denver Mint and should have received a "D" mintmark. An issue arose at the Denver Mint where the coin dies used to strike coins were being overworked and overused. Some coins would receive a weak "D" mint mark and in some very rare cases, the mint mark would be completely missing. In average condition, this coin is worth $888.
• 1931-S Lincoln Cent- Only 866,000 were minted, in average condition, this coin is worth $94.

Nickels (Key Date)

• 1885 Liberty Nickel
• 1886 Liberty Nickel
• 1912-S Liberty Nickel
• 1913 Liberty Nickel
• 1913-S Type II Buffalo Nickel
• 1916/16 Doubled Die Buffalo Nickel
• 1926-S Buffalo Nickel
• 1937-D "Three Leg" Buffalo Nickel
• 1950-D Jefferson Nickel

Dimes (Key Date)

• 1873-CC No Arrows Seated Liberty Dime
• 1894-S Barber Dime
• 1916-D Mercury Dime
• 1921-D Mercury Dime
• 1949-S Roosevelt Dime

Quarters (Key Date)

• 1896-S Barber Quarter
• 1901-S Barber Quarter
• 1913-S Barber Quarter
• 1916 Standing Liberty Quarter
• 1932-D Washington Quarter
• 1932-S Washington Quarter

Half Dollars (Key Date)

• 1878-S Seated Liberty Half Dollar
• 1892-O "Micro O" Barber Half Dollar
• 1916-S Walking Liberty Half Dollar
• 1921-D Walking Liberty Half Dollar
• 1938-D Walking Liberty Half Dollar

Dollar Coins (Key Date)

• 1804 Bust Dollar
• 1870-S Seated Liberty Dollar
• 1879-CC Morgan Dollar
• 1884-S Morgan Dollar
• 1889-CC Morgan Dollar
• 1892-S Morgan Dollar
• 1893-CC Morgan Dollar
• 1893-S Morgan Dollar
• 1894 Morgan Dollar
• 1895 Morgan Dollar 
• 1895-O Morgan Dollar
• 1895-S Morgan Dollar
• 1901 Morgan Dollar
• 1921 Peace Dollar
• 1928 Peace Dollar
• 1934-S Peace Dollar