Ink Errors and Printing Defects

Ink errors are printing defects involving the application, color, or quality of ink during the manufacturing process. These errors create visually unusual notes and are collected for their distinctive appearances.

Types of Ink Errors

Double Impression

The same design element is printed twice, slightly offset, creating a blurred or doubled appearance.

Example: The portrait appears twice, slightly displaced, so the image looks ghosted
Cause: The printing plate hits the paper twice due to mechanical malfunction
Value: Can be valuable, especially if the offset is dramatic and clear

Offset Printing (Transferred Image)

Wet ink from one printed sheet transfers to the back of the sheet above it, leaving a mirror image of the design.

Example: The reverse of a note shows a faint, backwards image of the face design
Cause: Sheets are stacked before ink is fully dry, or ink transfer occurs during handling
Value: Highly collectible; offset printing is dramatic and unmistakable

Ink Smears and Smudges

Ink smears across the surface of the note, obscuring portions of the design.

Causes: Ink roller malfunction, contamination on the printing plate, or equipment misalignment
Value: Depends on severity and visual appeal

Wrong Ink Color

An element prints in the wrong color, such as a serial number in black instead of green.

Example: Federal Reserve seal prints in green instead of black
Cause: Ink color is switched or wrong ink is loaded
Value: Very high, because color errors are difficult to fake

Ink Fold (Ink Transfer on Fold)

The paper is folded before printing, causing ink to transfer to the folded area. When unfolded, the note shows ink in unusual locations.

Example: A note unfolds to reveal serial numbers or design elements printed on the inside surface
Cause: Sheet is folded during or before printing
Value: Distinctive and collectible

Missing Color

One of the multiple ink colors fails to print, leaving the note incomplete.

Example: A note with red ink missing from the American flag on the back
Cause: One of the printing color stations fails
Value: Depends on which color is missing and how visible the absence is

Ink Shift or Registration Error

The front and back designs are misaligned—one side shifts relative to the other.

Example: The back design is shifted 1/8 inch to the left relative to the front
Cause: Paper shifts in the printing equipment between front and back passes
Value: Moderate, depending on how obvious the shift is

Ink Bleeding

Ink bleeds beyond the intended boundaries, creating a fuzzy or enlarged appearance for design elements.

Cause: Excessive ink on the printing plate or paper absorbency issues
Value: Depends on extent and visual impact

Quality Control for Ink Errors

The Bureau of Engraving and Printing monitors ink quality and color consistency strictly:

Ink is tested before and during printing runs
Color samples are taken and compared to standards
Registration (alignment) is checked continuously
Faulty notes are removed during inspection

Despite these controls, some ink errors escape to circulation, particularly older notes.

Valuation Considerations

Ink error values depend on:

Type and severity – Obvious errors worth more than subtle ones
Visual appeal – Beautiful or unusual color effects are valued higher
Condition – Uncirculated ink errors are significantly more valuable
Rarity – How many notes with this same error type exist?
Authenticity verification – Professional graders can distinguish genuine ink errors from post-production damage

Common Ink Error Price Range

Minor smears or shifts – $10-$100
Obvious double impressions – $100-$500
Clear offset printing – $200-$1,000
Wrong color printing – $500-$2,000
Multiple simultaneous errors – $1,000-$5,000+
Professionally graded ink errors – Values increase significantly based on grade

Authentication and Verification

Before assigning high value to an ink error:

Consult error note references
Compare the error to known ink error types
Consider professional grading for valuable examples
Verify the error is part of the printing process, not post-production damage