Collecting error currency is exciting. Like coins, most issues of U.S. currency make their way from the U.S. Mint to your wallet from your bank or from change for a cash payment. The designs, margins, and layouts of these bills will typically be uniform for their series.
Sometimes, a piece of paper gets folded as it reaches the printing press. And this creates a printing fold error.
That is just one of many kinds of currency errors. Most of these fit into one of several categories, like alignment, printing and inking, folds, and more. Some of these errors are subtle and require a keen eye for detail while others are easy to notice at a glance.
Printing Methods
Currency notes are printed one stage at a time. There are two primary components used to print currency: The printing plate and the impression cylinder. The printing plate contains ink and paper is used to keep this ink from the impression cylinder, which has one third of the design of a bill.
Printing Stages of U.S. Currency
It is worth noting that there are typically three printing stages for U.S. currency.
First Print
The first print that is made is the back of the note.
Second Print
The next step for printing currency is the portrait and border on the front of the note.
Third Print
The third and final step in printing currency is known as the overprint. This often includes seals for the Department of the Treasury and issuing Federal districts and the Federal Reserve serial numbers. After this step, notes are cut from sheets to their final size before being packaged for distribution.
Missing Print Errors
These errors occur when one of the above stages is missed. These notes are easy to spot, as they lack distinct design elements.
Missing First Print Error
Currency notes missing the reverse are notes that did not receive the first stage of printing when the reverse is printed. This may be caused by two sheets being fed into the printing press at once.
This error is straightforward and easy to identify. If the back of a note is totally blank, it probably missed its first stage of printing.
Missing Second Print Error
When a note does not receive its second stage of printing, it will appear normal on the reverse, but the obverse will have few details. This is also fairly straightforward and easy to identify as it went through the first and third stages of printing.
If you encounter a note with a fully designed reverse but an obverse that only has a green seal, a black seal, and serial numbers, it has missed its second stage of printing.
Missing Third Print Error
Notes with a missing print error that received the first and second stages of printing may be a little bit harder to spot in passing. At first glance, this note may appear to have the design elements of a typical U.S. note.
On a second glance, you will notice that this note is missing the black and green Treasury Department and Federal district seals to the left and right of the subject’s portrait. This note may also lack the signatures of the Secretary of the Treasury and the Treasurer.
Folding Errors on U.S. Currency
There are several kinds of folding errors you may encounter, and they occur in one of two ways, which dictates the error itself. There are folding errors where the fold is made before printing and those where the fold is made after the first printing.
Gutter Fold Errors
A gutter fold error is the result of a fold that becomes embedded in the paper before ink reaches the printer. As the paper note is later unfolded, it leaves a prominent gap in the printed design. Gutter folds often span the height of a currency note and can cause issues with the cutting of the note, as well.
Some gutter folds are large columns, and others are little more than small creases without ink.
Butterfly Fold Errors
Butterfly folds involve a fold, but this fold is typically on or near the corner of the note. As the note is cut after printing, and often unfolded by a patron of a bank or ATM, there is a little bit of paper that will extend out from the corner. Butterfly folds often feature an element of symmetric misalignment at or near the corner, causing a mild resemblance to a butterfly’s wings.
Like gutter fold errors, butterfly fold errors occur before inking. Butterfly folds are like gutter folds but do not typically run the full height of a note.
Printed Fold Errors
A printed fold error, also known as a fold over error, occurs after the first or second rounds of printing. In the case of printed fold errors, the reverse may print as expected, and then a fold happens, causing the second print to go over part of the obverse and the folded section of the reverse.
Folded print errors can also occur between the second print and the overprint. In this case, the reverse and part of the obverse will print normally, but the overprint will leave seals and serial numbers over the margin and onto the reverse, where the bill is creased.
Printing and Inking Errors on U.S. Currency
Offset Printing Errors
Offset printing errors take place when the inked plate makes contact with the impression cylinder. This causes the impression cylinder to take ink intended for the notes, which it can apply to the next note, creating a mirrored image on the wrong side of the note.
This error can occur on the obverse and reverse of the note. When the reverse of the note is inked with the inverted image intended for the obverse, it is considered offset printing from front to back. This would leave the portrait of George Washington’s face on the reverse of the $1, facing left and printed over the intended reverse.
Similarly, if the reverse of the note was inked inverted on the obverse of the note, it would be considered offset printing from back to print. There are partial variations of this error.
Overprint Currency Errors
There are three stages of printing U.S. currency notes. In those stages, it is possible for sheets of notes to be fed into the printer in the wrong orientation or facing the wrong direction. This causes an overprint error on the note.
Note that this error refers to the third step in the currency printing process and does not refer to the correction of an error in the way that an overdate does with coins. The overprint is also sometimes referred to as the letterhead.
Inverted Overprint Errors
An inverted overprint occurs when the sheets are oriented in the wrong direction in the overprinting stage of production. These will look like standard issue notes but the overprinting elements like seals and serial numbers will appear upside down on the note.
Another kind of inverted overprint error may initially be mistaken for a note missing the third print. They may blend in with the reverse design, but if the Treasury and Federal District seals are on the reverse and appear upside down, it is an inverted overprint error.
Insufficient Inking
When ink does not fill the plate as it should, it can result in faded areas on the bill. It can also cause smears and blots.
Cutting Errors
Cutting errors happen when sheets fall out of alignment during the cutting process. Both sides of the note will display this error. A small portion of an adjacent note is often visible on one of the margins.
Alignment Errors
Alignment errors, or misalignments can occur at any stage of the printing process. Like cutting errors, this error happens when a sheet falls out of alignment.
Misalignment errors in the first stage of the printing process will feature a reverse that is misaligned. The reverse will be too high, too low, or off-center. Similarly, misalignment errors in the second stage of printing will depict an obverse displaying misaligned positioning. The same is true of misalignment errors that happen in the third stage of printing, where the overprint will be out of alignment with the bill.
There are other errors that can happen on currency notes, such as doubled denominations, mismatched denominations, mismatched serial numbers, wet ink transfers, and more.
Collecting error currency is a way to add unique notes to any collection. Studying error currency teaches both an appreciation of their historical significance and the rarity of their imperfections shed light on the printing process.
