U.S. Inverts -- Lee's Illustrated Stamp Listopedia

When part of the design of a stamp appears upside down because of a printing mistake, it is called an invert. Inverts are often very rare and valuable to collectors. These are the nine varieties of United States inverts that have reached the public.

	Landing of Columbus	The 15-cent issue in a series of two-color stamps depicting American symbols and history. Three stamps in the series produced errors. (1869)
	Declaration of Independence	The 24-cent issue, after a painting by John Trumbull. (1869)
	Shield, Eagle and Flags	The 30-cent is the rarest of the 1869 inverts. (1869)
	Fast Lake Navigation	The first of three stamps in the Pan-American Exposition series which encountered printing errors that resulted in inverted centers. (1901)
	Fast Express	Only 158 copies of the 2-cent Pan-American Expo error are known to exist. (1901)
	Automobile	The vignette of an electric automobile is inverted in the 4-cent. (1901)
	Dag Hammarskjold	After a small number were discovered with the yellow background inverted, the Post Office intentionally reprinted the error, so that it is now worth little more than the rightside-up variety. (1962)
	Candle and Rushlight Holder	Nicknamed the "CIA invert" because 95 of the 100 existing inverts were sold to members of the CIA. (1979)
	Curtiss Jenny	The most famous of U.S. stamps is the airmail "inverted Jenny." (1918)

See also
Which Way is Up?	Smithsonian National Postal Museum's stories of inverts.
The Object at Hand	Smithsonian Magazine article on the Jenny invert.
Poor Jenny!	Report of how a $100,000 Jenny invert was vacuumed up by the cleaning woman.
Bibliography
Marzulla, Elena (ed.). Pictorial Treasury of U.S. Stamps, Omaha: Collectors Institute, 1974.
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