Stamp Condition and Grading Explained
Condition is the single biggest lever on what a stamp is worth. Two copies of the same issue, identical in catalog number, can differ by a factor of ten or more depending on how well the design sits within its margins, whether the original gum survives untouched, and whether the stamp has any faults. Learning the vocabulary is worth an hour of your time, because it is the language every catalog, dealer, and auction listing uses.
Mint, unused, and used — the first fork
- Mint never hinged (MNH) — never used, with original gum that has never had a stamp hinge applied. The premium category for most modern issues, and the one where the price gap over hinged examples is widest.
- Mint hinged (MH) — original gum, but a hinge has been applied and removed, leaving a mark or a thin patch. Older collections are overwhelmingly hinged, because that was simply how stamps were mounted before mounts became standard.
- Unused, no gum — never postally used, but the gum is gone, whether washed off, never applied, or lost to tropical humidity. Worth considerably less than MNH, though for some early classics unused-without-gum is the normal collectable state.
- Used — postally used and cancelled. For most twentieth-century material, used copies are far more common than mint, and worth less. For some classics the reverse is true, because far more were used than saved.
"Mint" strictly means with original gum as issued; in casual use people often say it when they mean "unused". If you are buying or selling, ask which is meant.
Centering: where the design sits
Stamps were perforated by machine, and the sheets did not always line up perfectly. How evenly the design sits within its four margins is centering, and it drives grading more than almost anything else. The traditional ladder runs roughly:
- Superb — design essentially perfectly centred, with even margins on all four sides.
- Very fine (VF) — clearly well centred, margins comfortably clear of the design. The benchmark most catalogs price against.
- Fine (F) — noticeably off-centre, but the perforations do not touch the design.
- Average / Good — markedly off-centre, perforations may touch or cut into the design. "Good" is, confusingly, one of the weaker grades.
For imperforate stamps the equivalent measure is margin width: four clear, even margins are prized, and a stamp "cut into" — where the scissors clipped the design — falls sharply in value.
Tip: never trim, re-perforate, or "tidy up" a stamp. Altering a stamp to improve its apparent centering is a recognised form of faking, and a stamp that shows evidence of it is worth less than the honest, poorly centred original.
Gum and hinges
For unused stamps, the gum on the back is part of what you are buying. Collectors distinguish original gum (OG) from regummed stamps, where new gum has been applied to imitate an unused example. Regumming is a deliberate deception and one of the more common ones, since it can turn a modest stamp into an apparently premium one.
Hinges — small folded paper tabs used to mount stamps in albums — leave a mark. A "hinge remnant" is leftover paper still attached; a "hinge mark" is the disturbance left after careful removal. Both reduce value against MNH, and both are perfectly normal on older material.
Faults: the things that quietly destroy value
A fault is any physical damage. Even small ones matter, and undisclosed faults are the most common reason a stamp sells for far less than the buyer expected.
- Thins — paper removed from the back, usually when a stamp was pulled off an album page or a hinge. Visible when held to light, and one of the most value-destructive faults there is.
- Creases and bends — a crease breaks the paper fibres and is permanent; a bend does not. Both show up under raking light.
- Tears, pinholes and scuffs — self-explanatory, and generally disqualifying for anything but space-filler status.
- Short, pulled or reperforated perforations — missing or repaired perforation teeth. Reperforating to fake better centering is a known deception.
- Toning, foxing and fading — brown spots from damp or acidic storage, and colour loss from light exposure. Both are usually irreversible.
Cancellations, when the stamp is used
For used stamps the cancellation is part of the object. A light, neat cancel that leaves the design readable is generally preferred to a heavy smudge that obliterates it. But this is not a simple rule: certain cancellations are themselves collectable — an unusual date, a notable post office, a maritime or railway marking, or a cancel from the first days of an issue can be worth more than the stamp. This is the field of postal history, and it is the reason you should never soak a stamp off its envelope before finding out what the envelope says.
Why professional grading exists
Because grading is judgement, and judgement can be self-serving, expertising services examine stamps, confirm genuineness, and issue certificates — sometimes with a numerical grade, sometimes encapsulated. For a valuable stamp, a certificate from a recognised body is often the difference between a sale and a stalled negotiation, and it typically pays for itself. For a common stamp it is not worth the fee.
What a photo can and cannot tell you about condition
A good photograph shows centering, margins, obvious perforation damage, the cancellation, and surface appearance — a genuinely useful subset. It will not reliably show a thin, a light crease, a repair, or regumming, and those are precisely the faults that matter most. An automated condition read is therefore best treated as a first impression: helpful for sorting a collection, not a substitute for examining a stamp in the hand under good light and magnification.
Read condition with Stamp Identifier
Stamp Identifier, coming soon to the App Store for iPhone, returns a condition read in plain language alongside its identification — noting what it can see about centering, cancellation, gum and visible faults, with a confidence level attached. It is an AI impression from a photograph, clearly labelled as such, and never professional grading or an appraisal.
