Some individual varieties of United States coins are so rare that they are not well known outside of specialists. The general collecting public may have some awareness of these issues, but tend to focus on the more widely available varieties. A case in point is the 1969-S Doubled Die Lincoln Cent. The issue features doubling which is just as dramatic as more popular and highly collected double dies, yet its significant rarity and infrequent availability serve as barriers to any widespread collectability.
Doubled dies are created during the process when coin dies are being produced from the hub. The design from the hub is transferred to the working dies, which are inverted, so to strike the coins normally. The transfer process happens with multiple impressions to bring up all the details of the design on the working dies. Occasionally the die or the hub will shift slightly during the transfer process. This will later be visible on the actual coins as distinct impressions with some measure of separation. Only certain parts of the design will appear doubled, usually most prominently in certain portions of the date or lettering.
Most doubled dies are minor and require magnification to be seen. However, a certain number of issues are more dramatic and can be detected without magnification. Among these are the 1955 and 1969-S Lincoln Cents and the 1916 Buffalo Nickel, each of which commands strong premiums on the market. Since every doubled die is only produced from a single die, the mintage is usually only a very small percentage of the overall mintage for the coin itself.
It should be noted that there is another type of doubling known as machine doubling. This occurs when the dies shift very slightly when a coin is being struck. Machine doubled coins occur more frequently and typically command little or no premium in the marketplace. These coins are usually identified by all devices and design elements being doubled, including the mintmark. The mintmark is not doubled on genuine doubled dies since the hubbing process occurs before the mintmark is punched into the die.
On a genuine 1969-S Doubled Die Lincoln Cents, the doubling can be found on the obverse die (thus the designation DDO, meaning Doubled Die Obverse). Strong doubling shows on both IN GOD WE TRUST and LIBERTY. Slightly less prominent doubling can be found on the date as well. The separation of the letters is extremely strong and can be easily noted without magnification. As previously mentioned, on genuine examples the mintmark and the portrait of Lincoln will show no doubling.