What are the most common state quarter errors?

Answer 1

Probably the most common error is the missing letter error. Small details, like letters, numbers, or small details in the design appear to be missing. This is usually caused by a foreign substance (like machine grease) that gets into the die and prevents the full striking of the coin. These errors seem plentiful, and collector interest is limited, so the value of these is generally no more than a couple dollars.

The most notable error is of course the "extra corn leaf" Wisconsin quarter. No one has come up with a definite answer on how this happened, but retail values have bounced around in a broad range from about $50 to over $200.

Also, there have been a number of different rotated-die errors reported. The most obvious is the 180-degree error on some Delaware quarters. This coin can be distinguished from a normal quarter by holding it in your hand and flipping it like the page of a book. Remember, all U.S. coins are supposed to be oriented so that the front and back sides point in opposite directions, so you have an error only if Washington and the rider (Caesar Rodney, FWIW) point the same direction when flipped like a book page.

Other SQ issues have been reported with lesser amounts of rotation, so it pays to check more than just Delaware quarters for this error.

Full 180-degree rotations retail for about $25. The price drops significantly with lesser amounts of rotation.