Choose a category below. Inside each category, terms are arranged vertically. Select any term to open its definition and examples.
REFERENCE CATEGORY
Types of U.S. Currency
Silver Certificate +
A form of United States paper currency originally issued with a legal relationship to silver held by the Treasury. Silver Certificates were produced in both large-size and small-size formats and are identified by the words Silver Certificate on the note.
Gold Certificate +
United States paper currency historically associated with gold held by the Treasury. Many issues are immediately recognizable by their gold-colored design elements.
United States Note / Legal Tender Note +
Paper money issued directly by the United States government rather than by a Federal Reserve Bank or National Bank. Collectors often refer to many of these notes as Legal Tender Notes.
Federal Reserve Note +
The principal form of U.S. paper currency today. Federal Reserve Notes are obligations of the United States and are issued through the Federal Reserve System.
Federal Reserve Bank Note +
A distinct historical currency type issued by individual Federal Reserve Banks. It should not be confused with the much more familiar Federal Reserve Note.
National Bank Note +
Currency issued by federally chartered National Banks and backed under the National Banking system. These notes identify the issuing bank and normally include its charter number, making town, bank and charter especially important to collectors.
Obsolete Banknote +
A broad collector term for paper money issued by state-chartered banks, businesses, municipalities and other issuers before the modern federal currency system became dominant.
Confederate Currency +
Paper money issued by the Confederate States of America during the Civil War, along with related state and local issues collected within the same historical field.
Emergency Currency +
Currency specially prepared or modified for extraordinary circumstances. Well-known U.S. examples include World War II Hawaii overprint notes and North Africa emergency notes.
REFERENCE CATEGORY
Understanding Currency Grades
70-Point Grading Scale +
Professional paper-money grading uses a numerical scale running from 1 through 70. Higher numerical grades generally indicate stronger preservation, with 70 representing the theoretical top of the scale.
Circulated +
A note showing evidence of handling or use in commerce. Circulated notes can range from heavily worn examples to pieces with only light folds or handling.
Uncirculated / Choice Uncirculated / Gem Uncirculated +
Terms used for notes that do not show normal circulation wear. Exact numerical ranges and terminology depend on the grading standard being used.
EPQ — Exceptional Paper Quality +
A PMG designation indicating that the note meets the company's standards for original paper quality for the assigned grade and has not been materially impaired by certain forms of restoration or processing.
PPQ — Premium Paper Quality +
A PCGS Banknote designation used for notes that meet its standards for original paper quality and eye appeal appropriate to the grade.
Details Grade +
A grading result identifying a note's general level of preservation while also noting a significant problem such as damage, repair, alteration or another condition that prevents a standard straight grade.
NET Grade +
A grading designation historically used by some services when a note has a problem serious enough to affect the final stated grade. The notation normally identifies the issue responsible for the reduction.
REFERENCE CATEGORY
Fancy Serial Numbers
Illustrative serials below show the pattern. They are examples, not photographs of specific notes unless stated otherwise.
Low Serial Number +
A serial number containing an unusually small numerical value. Collectors often pay increasing attention as the number approaches single digits or other very low values.
Solid Serial Number +
Every numerical digit is identical. Eight-digit solids are among the most immediately recognizable fancy serial-number patterns.
Radar Serial Number +
A palindrome: the serial reads the same from left to right and right to left.
Repeater Serial Number +
A sequence in the first half of the serial repeats in the second half. Your Andrea Doria repeater can eventually be shown here as a real Black Raven Collection example after it returns from grading.
Super Repeater +
A short repeating pattern continues across the entire serial. A common example is a two-digit sequence repeated four times.
Ladder Serial Number +
The digits progress in numerical order. Descending ladders, such as 87654321, are also collected.
Binary Serial Number +
A serial made from only two different digits. Some collectors reserve the term true binary for serials using only 0 and 1, while broader collector usage may call any two-digit pattern binary.
Rotator / Flipper Serial Number +
A serial made with digits that can still be interpreted when the note is rotated 180 degrees. The digits 0, 1, 6, 8 and 9 are typically involved, with 6 and 9 exchanging roles when rotated.
Star Note / Replacement Note +
A replacement note printed to substitute for a note removed during production. The star is part of the serial-number identification. A star note is not automatically a fancy serial number, although a star note can also have a fancy numerical pattern.
REFERENCE CATEGORY
Currency Errors
Gutter Fold +
A fold in the paper that occurs before or during printing and creates an unprinted or distorted channel when the fold is later opened.
Butterfly Fold +
A dramatic paper fold in which part of the sheet is folded over during printing, often leaving a triangular or wing-like unprinted area when unfolded.
Offset Transfer +
An unintended transfer of inked design elements, commonly caused when a printing surface contacts another surface without paper correctly positioned between them.
Cutting Error +
A note cut substantially away from its intended position, sometimes showing portions of an adjacent note or unusually large or small margins.
Misalignment +
One printing operation is noticeably shifted in relation to the paper or the other printed elements.
Obstructed Printing +
A foreign object or folded portion of paper blocks part of a printing operation, leaving an area with missing design.
Mismatched Serial Numbers +
The two serial numbers printed on the same note do not match because of a numbering-process malfunction.
Stuck Digit +
One digit in a serial-numbering mechanism fails to advance or align correctly, producing an abnormal serial-number result.
Error vs. Damage +
A genuine production error occurred while the note was being manufactured. Tears, stains, writing, trimming and alterations occurring after production are damage or modification rather than printing errors.
REFERENCE CATEGORY
Anatomy of a Banknote
Series +
The series designation identifies the design or signature combination under which a note was issued. It is not always the same as the exact year the individual note was printed.
Serial Number +
The identifying number assigned to a note. On many U.S. notes, letters are also part of the complete serial designation.
Treasury & Bank Seals +
Printed seals help identify the issuing authority, series or district and can be important in distinguishing varieties.
Signature Combination +
The printed signatures of Treasury officials or, on certain bank-issued notes, bank officers. Different signature combinations can define collectible varieties.
Block +
On many notes, the letter or letters surrounding a serial number form a block designation used to identify a particular printing sequence.
Plate Position +
A letter or number identifying where a note appeared on the larger sheet from which it was printed.
Face & Back Plate Numbers +
Small plate identifiers showing which printing plates produced the face and back of the note.
Friedberg Number +
A widely used catalog-reference number for varieties of United States paper money. Collectors commonly abbreviate it as Fr.
Charter Number +
The federal charter assigned to a National Bank. Charter numbers are fundamental identifiers when researching and collecting National Bank Notes.
REFERENCE CATEGORY
Collector & Currency Terminology
Provenance +
The documented history of ownership, custody or origin of an object. Strong provenance can be particularly important when a note is connected to a historical event.
Pedigree +
A recognized association with a notable former owner, collection or source. The term is often used more narrowly than provenance.
Census +
A compiled record of known surviving examples of a particular note, bank, type or variety.
Population +
The number of notes reported by a grading service at a particular grade or across all grades. Population data should not automatically be treated as an exact count of unique surviving notes.
Rarity +
A measure of how scarce a note or variety is. Rarity can refer to known survivors, estimated survivors, availability in the marketplace or a published rarity scale.
Mule +
A note printed using a combination of face and back plates from different plate-size or production configurations, creating a collectible plate-number variety.
Remainder +
An otherwise prepared note that was never fully issued for circulation, often lacking signatures, serial numbers or other elements normally added before release.
Proof +
A specially produced impression made to evaluate or preserve a banknote design rather than for normal circulation.
Specimen +
A note produced or marked as a sample rather than intended for circulation. Specimens may have special serials, overprints, perforations or other identifying features.
Scrip +
A form of locally or privately issued paper substitute for money, often redeemable only under particular conditions or by a specific issuer.
Cancellation +
A mark, punch, cut or other intentional action used to show that a note or financial instrument has been redeemed, retired or otherwise invalidated.
External Collector Resources
PCGS Banknote · PMG · Society of Paper Money Collectors
Independent external resources. No affiliation or endorsement is implied.
Last updated September 2026.