Airplanes are supposed to fly right side up, correct? If you’ve ever seen the rare 1918 “Inverted Jenny” United States stamp, you may think otherwise, or, at the very least, may be confused. These rare stamps show a plane that appears to be flying upside down!

In 1918, the United States produced a 24-cent postage stamp honoring the Curtiss JN-4 airplane, known at the time as a “Jenny”. It was one of the first examples of an air mail stamp. Air mail, which was transported via airplane, could arrive at its destination much faster than by ground mail. At 24 cents, air mail stamps were far more expensive than the typical three cent postage stamps of the time. The Jenny stamp itself has vivid red framing with a white background. The airplane is blue. The stamps were printed in sheets of 100 and the red and blue colors within the stamp required two trips through the printing press. It could have been that a sheet of printed frames was put into the press upside down or the printing plate used to stamp the plane itself was upside down. Whatever the case, it is thought that only a single sheet of Inverted Jenny stamps ever made it past the printing press. The vast majority of these stamps were printed correctly.

That said, word of the erroneous sheet of stamps spread quickly and collectors rushed to their local post offices. One lucky collector named William Robey was astonished to find the treasure at his local post office. He quickly purchased it for $24 and promptly sold the sheet to a prominent stamp collector for $15,000 - an enormous sum of money at the time. It was sold again to a collector who thought the stamps would be worth more individually and thus, detached many of the stamps from the original sheet and sold them to other collectors. Many of the buyers, however, hinged the soon-to-be-priceless stamps. Hinging was a common practice at the time that collectors used to display stamps in their stamp albums. Hinging stamps damages the original gum on the back of the stamp that would be licked to adhere to a letter or package. A hinged stamp cannot be in mint condition. Only six of the original stamps are unhinged.

Over time, many of the original stamps have been damaged, hinged, or destroyed, leaving few in mint condition. Furthermore, many counterfeit versions are thought to exist. Others have been stolen or disappeared entirely. As the prices of the stamps rose, collectors tried to document each of the original stamps. In 2018, one of the long lost Inverted Jennies was found again. It was unhinged! On November 15th, 2018, it was sold at auction for just under $1.6 million dollars!