Gum, hinges, thins, repairs, watermarks, paper, and expert marks often live on the reverse.
The practical lesson
- Always request a full back image.
- Never assume “mint” means original gum.
- Old hinges and dealer marks are evidence, not automatically defects.
What to do next
Photograph the object, preserve its context, convert the description into measurable traits, and compare only genuinely similar items.
Compare current collector listings
Use listings to study descriptions, scans, certificates, and market supply. Asking prices are not completed-sale evidence.
Compare collector listings