Treskilling Yellow （瑞士"三先令"）

Treskilling Yellow

Estimated value: Much higher than US$3.14 million

The Treskilling Yellow is a Swedish postage stamp, which holds the world's record auction sales price for a single postage stamp.

The normal three-skilling stamp, printed in Sweden, should be green, whereas the eight-skilling stamp was printed in yellow. However, due to an unknown error in 1855, (most likely because the three-skilling plate was accidently replaced by an eight-skilling one), the three-skilling stamp was printed in yellow, creating the precious Treskilling Yellow stamp.

The only known copy in existence of the Treskilling Yellow, was discovered by a schoolboy named Georg Wilhelm Baeckman in 1886, while going through his grandparents' attic.

The stamp made headlines in 1984 when it was sold for 977,500 Swiss francs (US$1.07 million). At a 1990 sale, it made over US$1 million, and then in 1996 it sold again for 2.875 million Swiss francs. Each successive sale meant a world record worth for a postage stamp.

Being one of the most expensive objects in the world, the stamp was auctioned off once again in Geneva, Switzerland, in May 2010. The exact price and the identity of the buyer were not disclosed, but the auctioneer David Feldman released that "it is more expensive than any other single postage stamp in the world."