Treskilling Yellow: Sweden's Unique Colour Error

The Treskilling Yellow is a Swedish three skilling banco stamp from 1855 that came off the press in yellow-orange instead of blue-green, and it is the only example known. That single fact has made it one of the two most valuable stamps in the world alongside the British Guiana 1c magenta.

Its best-documented price is 2,880,000 Swiss francs at David Feldman in Geneva in 1996, then the highest price ever paid for a single stamp. It had made 977,500 Swiss francs at Feldman in 1984 and passed the million-dollar mark in a 1990 sale. Feldman offered it again in Geneva in 2010, where it went to the investor Armand Rousso, and in 2013 it passed privately to the Swedish businessman Count Gustaf Douglas.

Unlike most record stamps, this one has spent decades being argued about rather than quietly appreciating, which is part of why its price history is uneven.

Sweden's first stamps, issued in 1855, used a set of denominations with fixed colours. The three skilling banco was blue-green; the eight skilling banco was yellowish orange.

Printing plates of the period were assembled from individual stereotypes, one small cast block per stamp position. The accepted explanation for the error is that a stereotype in the eight-skilling plate was damaged or broken and was replaced with a three-skilling stereotype by mistake. The plate then printed a sheet of eight-skilling stamps in the correct yellow-orange ink, with one three-skilling design among them.

That is why a single stamp exists rather than a whole sheet, and why the colour is exactly right for a different denomination rather than being an odd shade. Colour errors of this specific kind — a correct ink applied to a wrong design — are among the hardest to fake convincingly, because the ink has to match the other value precisely.

The stamp entered the record in 1886, when a Swedish schoolboy, Georg Wilhelm Backman, went through old covers in his grandmother's attic and found it. He sold it to a dealer, and it moved through a series of well-known collections over the following century.

Its authenticity has been contested more than once. At one stage the Swedish Postal Museum took the position that it was a forgery. Two separate commissions examined it, and both concluded that the stamp is genuine — an unusually public dispute for an item of this rank, and one reason its provenance file is thicker than most.

For a buyer the lesson generalises. A rarity's paperwork is not a formality: expert committee opinions, museum examinations and published census entries are what a seven-figure price actually rests on.

Sweden's 1855 first issue in its correct colours is scarce and valuable in its own right, particularly on cover, but it is a collectable series rather than a unique object. Later nineteenth-century Swedish issues — the ring types, the Oscar II definitives — are common in mixed collections and inexpensive.

A yellow or orange Swedish stamp is almost always one of these: an eight skilling banco in its correct colour, a later orange definitive, or a toned or chemically altered stamp whose colour has changed with age or exposure. Light, damp and cleaning agents all shift inks, and a faded blue-green can look surprisingly warm.

Any stamp that appears to be a colour error needs the same treatment as a grill or an invert: an expertising certificate before anyone discusses a price. Our guide to stamp errors and varieties explains which colour differences the catalogues actually recognise.

Colour is the least reliable thing to judge by eye. It changes with the light you are standing in, with the age of the paper, and with whatever the album page next to it is doing to your perception.

Three habits help. Compare against a known normal example of the same issue, side by side, rather than against memory. Use daylight or a colour-corrected lamp, not a warm household bulb. Look at the back of the stamp as well: ink that has soaked through unevenly, or paper that is browned overall, usually means the stamp has been exposed rather than misprinted.

Photograph the stamp and the app identifies the issue, which gives you the normal colour to compare against before you start hoping for an error. For storage that prevents colour change in the first place, see storing and caring for stamps.