The Inverted Swan, a 4-pence blue postage stamp issued in 1855 by Western Australia, is the world's first invert error (technically a "frame invert").

In 1854, Western Australia issued its first stamps, featuring the colony's symbol, the Black Swan, as did all WA stamps until 1902. While the 1d black was engraved in England by Perkins Bacon, other values, including the 4d blue, were produced by Horace Samson in Perth using lithography, and with different frames around the swan design for each value.

In January 1855, additional 4d stamps were needed; but when Alfred Hillman brought the stone out of storage, he found that two of the impressions were damaged, and had to redo them. One of the replaced frames was tilted, and the other accidentally redone upside-down. The stone's block of 60 was transferred four times to make the printing stone, and 97 sheets were printed before Hillman discovered the mistake and corrected it, resulting in a total of 388 errors being printed.

However, the errors went unrecognized and unreported for several years, and only 15 complete copies, plus a partial in a strip, have survived. No unused copies are known.

One copy was discovered in Ireland in the 1860s, acquired by the Duke of Leinster, and bequeathed to Ireland in 1897. It is on display at a museum in Dublin. Other copies are in the Tapling Collection of the British Museum, and at a museum in Sydney.

Prices have been variable, with one copy realizing US$80,000 in a 1980 auction, and another going for $37,500 in 1983.

Reference

• Philatelic Gems 1 (Amos Press , 1989)