How to Use a Loupe and UV Light to Pre-Screen Currency Before Submission to PMG or PCGS

Every experienced currency collector has a story about a note they submitted with high hopes, only to receive it back with a grade that cratered its value or, worse, a “details” designation for a flaw they never noticed. A pressed fold here, a hidden stain there, a tiny ink smear that only reveals itself under the right light. The professional grading services, PMG (Paper Money Guaranty) and PCGS Currency, catch everything. Their graders use high-magnification loupes, raking light, and ultraviolet lamps as standard tools on every single submission. The good news is that you can use those exact same techniques at home before you spend a dime on grading fees.

Why Pre-Screening Matters: The Real Cost of Skipping It

At $25 to $30 per note at economy tier rates, grading fees add up fast. Submit ten notes in a single batch and you are already at $250 to $300 before any special handling, insurance, or shipping. If three of those notes come back with “Net” grades or “Details” qualifiers for problems you could have spotted yourself, you have essentially paid full price for a label that hurts resale value. A circulated 1934A $1,000 Federal Reserve Note in PMG VF-35 might retail for $3,500, but the same note graded VF-35 EPQ can push $4,500 or more. Conversely, a “Details: Pressed” designation on what appeared to be a Choice Very Fine example can cut the value nearly in half compared to a problem-free grade.

Pre-screening is not about trying to fool the graders. It is about making informed submission decisions and learning to see your notes the same way professionals do. Let’s build that skill set systematically.

Building Your Pre-Screening Kit

Choosing the Right Loupe

The loupe is your primary inspection tool. For paper money, a 5x to 10x jeweler’s loupe hits the sweet spot. At 5x you get excellent field of view for examining overall fiber integrity, counting major folds, and spotting corner damage. Bumping up to 8x or 10x lets you examine printing quality, check for ink transfers or smears, and look closely at serial numbers and Treasury seal sharpness on older notes.

Avoid cheap single-element loupes; they distort color and introduce chromatic aberration at the edges, which can actually mask defects. Spend $30 to $60 on a quality triplet loupe from brands like Bausch and Lomb, Belomo, or Eschenbach. A triplet loupe uses three cemented glass elements to produce a flat, color-correct field of view. The Belomo 10x triplet, widely available for around $40, is a particular favorite among currency graders for its wide field and distortion-free image.

LED-illuminated loupes are convenient, but be aware that built-in white LED light comes from a fixed angle. You will want to supplement this with a moveable raking light source (described below) to reveal folds and surface disturbances that front-on illumination hides entirely.

Raking Light: The Fold Revealer

Folds are the single most common reason a note drops a grade tier or receives a “Details: Pressed” designation. A skilled presser can iron out a crease so thoroughly that it is nearly invisible under normal lighting. But the fiber of the paper is permanently disturbed; the cellulose structure has been crushed and realigned. Under raking light, where illumination strikes the note at a very shallow angle (roughly 10 to 15 degrees from the surface), that disturbed area catches light differently from the surrounding paper and becomes immediately visible as a subtle ridge or shadow line.

You do not need expensive equipment for raking light examination. A simple adjustable-arm LED desk lamp works perfectly. Place the note flat on a clean, dark surface and bring the lamp down to nearly horizontal. Slowly rotate the note through 360 degrees while keeping the lamp fixed. This technique is the same one PMG and PCGS graders use on large-size notes and high-denomination small-size notes where pressing is most commonly attempted.

Selecting a UV Lamp

Not all ultraviolet lamps are created equal, and this matters enormously for currency authentication and grading evaluation. You need a longwave UV lamp operating at 365 nanometers. Shortwave UV (254 nm) is used primarily for detecting certain counterfeit security threads but is hazardous to eyes and skin and inappropriate for casual collector use. The inexpensive 395 nm “UV” flashlights sold on mass-market retail sites are actually near-UV or violet-spectrum lights. They will make some things fluoresce, but they miss the specific fluorescence signatures that trained graders rely on and can give false confidence.

Invest in a proper 365 nm longwave UV lamp. The Convoy S2+ flashlight fitted with a 365 nm LED module has become extremely popular in the collector community for around $30 to $40. For bench work, the UVBeast V3 or the Spectroline ENF-240C provide broad, even illumination across the full note. Always use UV-blocking safety glasses when working with any 365 nm source for extended periods.

What to Look For Under UV Light

Paper Fluorescence and Washing

Federal Reserve Notes printed after 1929 use paper manufactured with specific fiber and composition standards that fluoresce in a characteristic dull, muted way under 365 nm UV. The paper should look relatively dark and non-reactive, with the embedded red and blue security fibers glowing faintly. If a note glows brightly white or with a brilliant blue-white fluorescence, it is almost certainly a reproduction, a fantasy note, or has been washed with a brightening agent or bleach. This bright fluorescence is an immediate “Altered” or “Counterfeit” designation at any grading service.

Chemical washing is used by unscrupulous sellers to remove stains from circulated notes, attempting to make them appear uncirculated. Under UV, washed areas typically show uneven fluorescence patterns or blotchy patches where the chemical has altered the paper’s optical properties. A classic example from the collector market involves Series 1934 and 1934A $100 Federal Reserve Notes, many of which circulated heavily during World War II and occasionally surface chemically cleaned to prey on less experienced buyers.

Stains, Foxing, and Hidden Repairs

Many organic stains, including food residue, certain inks, and biological material, absorb UV radiation and appear as dark spots or patches against the note’s normal fluorescence. These are the stains most likely to earn a “Details: Staining” designation. Foxing, the brown spotty discoloration common on large-size notes from the 1861 to 1928 era, often fluoresces distinctively under 365 nm light even before it becomes visible to the naked eye in white light.

Paper repairs are among the most critical finds. A small tear that has been mended with rice paper or archival tissue and then inpainted will almost always show up under UV as a patch with dramatically different fluorescence from the surrounding note. The adhesive used in professional restoration also typically fluoresces in ways that betray the repair. On a note like a Series 1880 $100 Legal Tender (Fr. 168 through Fr. 171), where problem-free examples in Fine-12 can bring $2,500 to $4,000 at auction, discovering a repaired tear before submission rather than after can save significant disappointment and fees.

Security Thread and Watermark Verification

Starting with Series 1990 small-size Federal Reserve Notes, the Bureau of Engraving and Printing incorporated embedded polyester security threads that fluoresce in denomination-specific colors under UV. The $5 fluoresces blue, the $10 orange, the $20 green, the $50 yellow, and the $100 pink-red. This serves dual purposes for the pre-screening collector: first, it instantly confirms the note is genuine currency rather than a high-quality reproduction, and second, it tells you the security thread is intact and properly positioned, which matters for high-grade submissions of post-1990 uncirculated notes.

The Loupe Examination Sequence

Establish a consistent examination routine so you never miss a critical area. Work through the following sequence on every note before making a submission decision.

Step 1: Margins and Borders

Under 8x to 10x magnification, examine all four margins. Note the centering carefully. PMG and PCGS both deduct for poor centering, and what looks acceptable to the naked eye can reveal itself as notably off-center under magnification when compared against the printed border lines. On large-size notes, centering issues were extremely common given the sheet-fed printing technology of the era. For small-size notes in the Gem Uncirculated (65 EPQ to 68 EPQ) range, centering must be exceptionally good on all four sides.

Step 2: Corner Integrity

Corners are the most vulnerable part of any note and the first place experienced graders look when a note is presented as Extremely Fine (40) or better. Under 10x magnification, a corner that appears sharp to the naked eye may reveal micro-folds, slight rounding of the fiber tips, or a pressed corner tip that has been worked back into shape. Any of these conditions will push the grade down or trigger a “Details” qualifier. On pre-Federal Reserve issues such as National Bank Notes and Silver Certificates, pay particular attention to corner fiber separation, where the layers of the note’s paper have begun to split at the very tip.

Step 3: Surface and Body

Using both the loupe and your raking light, systematically examine the note’s body in overlapping sections, moving from left to right across both the face and back. You are looking for folds (sharp or soft), counting pinholes (very common on pre-1900 issues that were pinned together in bank bundles), identifying any soiling, and checking for ink loss or abrasion. Ink abrasion, where the fine lines of intaglio printing have been worn smooth, is common in the center of frequently handled notes and will cost grade points even when no formal fold is visible.

Step 4: Printing Quality

Under magnification, examine the intaglio printing (the raised ink that gives US currency its distinctive tactile feel) for completeness and sharpness. On Series 1928 through 1934D small-size notes, the fine portrait engraving lines should be clean, distinct, and free of ink smears or press fills. An ink smear, where wet ink spread during the printing process, is a manufacturing defect that both grading services note. While it does not necessarily drop a note to “Details” status, it can prevent the coveted EPQ (Exceptional Paper Quality) or PPQ (Premium Paper Quality) designation, which adds significant value to certified notes.

Making the Submission Decision

After completing your loupe and UV examination, you have actionable intelligence. For notes that passed cleanly, assess whether the expected grade justifies the fee. A clean, well-centered Series 1963A $1 Federal Reserve Note in Gem Uncirculated might grade PMG 66 EPQ and retail for $18 to $25 slabbed. The $25 grading fee makes submission economically neutral at best. But a clean Series 1928B $2 Legal Tender (Fr. 1504) in the same condition, where PMG 66 EPQ examples bring $200 or more, makes excellent economic sense.

For notes that showed issues under examination, your decision depends on the severity. A note with a single light vertical fold is circulated and should be submitted only if the variety or signature combination justifies the fee at a VF or EF grade. A note showing UV-positive washing or a repaired tear should generally not be submitted, as the “Details” or “Altered” designation will result in a slab that actively hurts resale value in most cases.

Conclusion: See What the Graders See

The goal of pre-screening is not to become a competing grader; it is to make smarter decisions with your collecting budget. PMG and PCGS graders have examined hundreds of thousands of notes. Their eye is trained and their standards are codified. But the tools they use, the loupe, the raking light, and the 365 nm UV lamp, are fully accessible to any collector willing to invest $60 to $100 in equipment and a few hours in practice.

Start with your most recent acquisition. Run through the full examination sequence outlined above. Then compare your assessment to how you would have graded it purely by eye before reading this guide. That gap, between casual observation and systematic examination, is exactly what grading fees are paying someone else to close. The more you narrow it yourself, the more confidently you can build a collection of certified notes that represent genuine value rather than expensive surprises.