Errors and varieties: what actually counts

Guides · 5 September 2026

Two words get used interchangeably and mean opposite things. An error is something that went wrong during the making of one item or a small run. A variety is a difference built into the die or plate itself, so it repeats on every item made with that tool. The first is an accident, the second is a fingerprint of the production – and almost everything else people find is neither, just damage that happened afterwards.

Why the distinction decides everything

A variety is repeatable: once identified, collectors know how many exist in principle and what to compare against, and it earns a catalogue line of its own. An error is not repeatable, so each one is judged on its own – how far the process went wrong, whether it escaped into circulation at all, and whether it can be proved. That is why a documented variety can be looked up and a claimed error usually has to be demonstrated.

On coins

• Varieties. Differences of the working die: the shape of a figure, the position and count of small elements, the spacing of lettering. These are read exactly as described in the guide to the circulation series and its die varieties.
• Striking errors. Off-centre strikes, double strikes, a blank that was never struck, a coin struck on the wrong blank.
• Die state, not variety. A die that cracked or wore during use leaves raised lines or soft detail. It is a stage of the die's life, and it is described separately from a true variety.
• Not errors at all. Rim knocks, scratches, corrosion, drilled holes and anything caused after the coin left the press.

On stamps

• Varieties. Plate flaws that repeat in the same position on every sheet, retouched areas, differences of perforation or paper between printings.
• Errors. A missing colour, an inverted element, a wrongly perforated sheet, an overprint applied upside down or to the wrong stamp.
• Overprints deserve care. An overprint is a normal production step, as on the 1961 stamp above – it becomes an error only when it is misplaced, inverted or doubled, and forged overprints are common precisely because the base stamp is cheap.
• Not errors at all. Trimmed perforations, thin spots from hinges, creases and colour changes caused by light or damp.

The three questions to ask before getting excited

1. Does it repeat? Find a second example. If the same feature appears in the same place on another item, it is a variety. If not, it may be an error – or damage.
2. Could it have happened afterwards? Most surprising features are post-production: heat, pressure, chemicals, a coin in a machine, a stamp in a damp album. Assume this first, because it is usually true.
3. Is the base item cheap? If it is, treat a spectacular feature with suspicion. Manufactured rarities are made from common material, and the check is the same as in the guide to telling an original from a copy.

How to record a find

• Photograph it beside a normal example of the same issue, in the same light and at the same angle.
• Note the exact position of the feature – on stamps, its place in the sheet if you know it; on coins, the clock position.
• Do not clean, press or otherwise improve the item. Anything you do makes the find harder to prove.
• Keep the item and the evidence together; an unlabelled oddity in a box is worth nothing to the next person.

What the archive offers

Comparison is the whole method, and that is what an open archive is for: 6,382 Soviet stamp issues of 1918–1991 with catalogue numbers and 855 Soviet coins, most shown from both sides. A suspected variety only becomes a variety when you can put it next to a normal example and point at the difference.

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