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Types of Mint Errors

Mint error coins are the result of a mistake in the manufacturing process at the United States Mint. Like any product produced by the billions, mistakes are made and missed, allowing error coins to be released into general circulation. Many types of mint errors can be found in the change in your pocket, especially pennies, state quarters and the presidential dollars. Minor mint errors will sell for only a few dollars; however, truly rare and collectible mint errors can fetch thousands of dollars at auction.

Broadstrikes
- Broadstrikes occur when dirt or debris gets lodged between the plate collar and the lower die, causing it to stick. The design may be slightly off-center but the date, lettering and portrait are all intact and visible on the coin. Because of the pressure of the die press, it will look like a bowl. The broadstrike is not a favorite of collectors, but it is still important.
Blank Planchet
- A blank planchet is a coin that runs through the striking press but does not get struck by the die. Type One variety blanks are freshly cut in the blanking press, which feeds the striking press. Type Two blanks have slightly raised rims because they went through a softening process but zipped through the striking press. This is a common error and can be found in rolls of new coins. Again, not valuable, but collectible.
Clipped Planchet
- A clipped planchet error happens when the metal sheet that the blanks are made from shifts during the cutting process. When the coin is pressed, it comes out with a piece of it missing. Clipped planchets can be straight, ragged or curved. These are moderately collectible.
Off Center
- Off-center strikes are the most common and collected mint errors. This happens when the coin blank does not land properly on the collar when fed into the press and only part of the coin is stamped on the blank. How much of the coin is visible (i.e., 40 percent) determines a large part of its value.
Doubled Die
- Most doubled die errors are machine made and look flat and smooshed, rather than raised and clearly doubled. These are not collectible and coin collectors consider them damaged coins. However, doubled die errors made prior to the U.S. Mint going completely to machine and computer controlled sorting of coins, are highly collectible. The most famous doubled die mint error is the 1955 Lincoln cent with its slightly misaligned date. This coin and a few others can bring bids of well over $1,000 at auction, depending on the condition of the coin.
Wrong Metal
- Wrong metal mint errors occur when a blank planchet for one denomination is fed to a press meant for another denomination. For example, a penny planchet may be fed into a coin chamber for dimes resulting in a penny being stamped on a dime planchet. These are collectible mint errors.
Tips
- The value of a mint error coin is influenced by condition, quality and rarity of the strike.
  
  Never clean coins you suspect may be valuable. Have them appraised, as is, by a reputable dealer or by one of the major coin-grading services that can also clean, appraise and seal the coin.

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