Reperforation, regumming, cancel removal, repairs, color change, and added overprints can transform appearance.
Identification rule: record what is visible before assigning a catalog number or value.
What to record
- Edge fibers and hole geometry.
- Gum texture, pooling, cracking, and perforation tips.
- Backlighting for thins, tears, and filled areas.
- Ink interaction and overprint position.
What commonly causes mistakes
- No single home test proves authenticity.
- Chemical tests can damage stamps.
- Reference scans can differ by production position.
A practical research sequence
- Identify the exact genuine reference.
- Inspect front, back, edges, and gum.
- Compare under magnification and appropriate lighting.
- Seek expertization when value depends on the result.
Condition and value
Value depends on exact identity, condition, centering, gum or cancellation, faults, certification, demand, and a defensible comparison set. A famous design does not automatically make an individual example rare.
Compare current collector listings
Use listings to study descriptions, scans, certificates, and market supply. Asking prices are not completed-sale evidence.
Compare collector listings