Two copies of the same stamp can differ in value tenfold because of condition alone. Collectors use a shared vocabulary to describe it. Here is what those terms mean.
Mint or used?
| Term | Meaning |
|---|---|
| MNH (mint never hinged) | Unused, with full original gum and no hinge mark. Usually the most valuable for stamps after about 1940. |
| MH / MLH (mint hinged / lightly hinged) | Unused, but a stamp hinge was once attached to the gum and left a mark. |
| NG / No gum | Unused, but the gum has been lost or removed. |
| Used | Went through the mail and has a postmark (cancellation). |
| CTO (cancelled to order) | Cancelled by the post office without being mailed, often in bulk for the collector market. Usually has full gum and a neat corner cancel. Normally worth less than properly used copies. |
Which one is "better" depends on the stamp. For many 19th-century issues, unused copies are rarer and more valuable. For some others, a genuinely used copy is scarcer than a mint one.
Centering
Centering describes how evenly the design sits within the perforations. US grading in particular uses these terms:
- Superb. Perfectly centred with wide, even margins.
- Extremely Fine (XF). Almost perfectly centred.
- Very Fine (VF). Slightly off-centre, but the design is well clear of the perforations.
- Fine (F). Noticeably off-centre, but the perforations don't touch the design.
- Average / Good / Poor. The perforations cut into the design.
Postmarks on used stamps
A light, clear cancel that leaves the design readable is preferred. A socked-on-the-nose cancel, where the full circular date stamp sits squarely on the stamp, is prized by some collectors because it shows the town and date. Heavy, smeared or pen cancels usually lower value, although pen cancels can mean fiscal (revenue) use. See types of stamps.
Faults that reduce value
- Thins, where paper was pulled away, often by a hinge
- Tears, creases and missing or short perforations
- Stains, toning ("foxing") and faded colours
- Repairs, regumming and reperforating, which are sometimes done to deceive
Hold a stamp up to the light, or place it face down in watermark fluid, to reveal thins and repairs.
Keep stamps in good condition
- Store stamps in stock books or mounts, not with hinges, if they are MNH.
- Keep albums upright, away from sunlight, heat and damp.
- Handle stamps with tongs.
Scanning a stamp in AI Stamp records the stamp together with its condition notes, so your collection's details stay in one place.