May 6, 1840 was the first day of the first stamp. Many inventions are derivative. The automobile, for instance, didn’t appear in fully developed form. Many engineers and inventors from many countries worked on various car platforms, improving the work of previous designs, to get the point of a fully functioning modern car. This type of model is true for most inventions. Some, however, are nearly perfect when they are first conceived and are only tweaked around the edges. For 173 years, the only change to Rowland Hill’s original stamp has been the addition of perforations. Perhaps only the light bulb has kept as close to its original design and continues to serve an important function.
The Penny Black is not a rare stamp. Over 68 million were printed. Conventional philatelic wisdom has always held that 1% is a good estimate for the number of stamps that have survived to the current time from any nineteenth century issue. Most people who do these back of the envelope estimates of stamp survival rates think that the number of Penny Blacks that were saved is much higher than that.
The stamp signified a revolution. Postage rates were slashed, and for the first time the lower middle class could afford to correspond with family and friends for anything but birth and death announcements. Correspondence from family and friends had a high survival rate in the nineteenth century. Letters were read and reread, often over a period of years. Most letters in this period were folded letters (a large sheet of paper written on and folded over to form its own envelope, because envelopes were expensive and people didn’t have money to burn). The folded letters were stamped with Penny Blacks so that when the letters were saved the stamps were saved too. Perhaps one million Penny Blacks survive, though as these correspondences were dispersed in the late nineteenth and early twentieth centuries most of the stamps were spoked off the envelopes. Price though is determined not only by supply but also by demand. As the first stamp, the Penny Black has been in demand worldwide and always has been. The stamp has been promoted in China, and many people who own no other postage stamps own a copy of the Penny Black.