Paper money is surprisingly fragile. Light, humidity, oils from your skin, and improper handling can all degrade a note's condition — and reduce its value permanently. The good news: with simple, inexpensive precautions, you can preserve your notes for decades.
The Fundamentals: What Destroys Paper Money
Four factors cause the most damage to banknotes:
- ✦Humidity — High moisture causes mold, foxing (brown spots), and paper degradation. Low humidity causes brittleness.
- ✦Light — UV light fades ink and yellows paper over time. Even brief exposure adds up.
- ✦Heat — Accelerates chemical degradation and promotes mold growth.
- ✦Physical handling — Oils, dirt, and acids from skin transfer to the note surface. Each touch causes microscopic damage.
Proper Storage Materials
Not all protective sleeves are equal. Use archival-quality materials specifically designed for paper money:
- ✦Mylar D (polyester) sleeves — The gold standard. Chemically inert, crystal clear, and durable.
- ✦Polyethylene sleeves — A good, inexpensive alternative. Avoid PVC (vinyl) sleeves at all costs — they off-gas plasticizers that destroy paper over time.
- ✦Acid-free paper or cardboard backing — If using top-loaders or albums, ensure all paper components are acid-free and lignin-free.
- ✦Currency albums — Look for albums specifically marketed as acid-free and archival-safe.
Climate and Environment
The ideal environment for paper money storage:
- ✦Temperature: 65–70°F (18–21°C) — stable and cool.
- ✦Humidity: 45–55% relative humidity — use a hygrometer to monitor.
- ✦Light: Complete darkness preferred. Use archival boxes or a safe.
- ✦Air quality: Away from chemicals, cleaning products, or off-gassing materials.
Handling Your Notes
When you must handle ungraded notes, wear clean white cotton gloves or hold the note by its edges only. Never fold, bend, or press a note. Lay notes flat — never roll or store them upright. For high-value notes, professional grading and encapsulation in a tamper-evident slab (PMG or PCGS) provides the best long-term protection while making the note displayable and verifiable.
The One Rule You Must Never Break
Never clean a banknote. What looks like improvement to the eye — removing a stain, restoring crispness — is immediately apparent to any experienced collector or grader. Cleaning reduces a note's grade, removes its EPQ or PPQ designation eligibility, and makes it unsellable to serious collectors at its true value. A note with original dirt is always worth more than a cleaned one.