No one can criticize you for calling this "rare."!

http://www.theglobeandmail.com/news/world/this-stamp-is-set-to-become-most-expensive-tiny-thing-in-the-world-again/article19193363/

"Sotheby’s predicts the 1856 British Guiana One-Cent Magenta could bring between $10-million and $20-million (U.S.) when it goes on the auction block Tuesday. That would make it the most expensive object in the world, by size and weight, according to Sotheby’s.

"Measuring 1 inch-by-1 1/4 inches, the One-Cent Magenta hasn’t been on public view since 1986. It’s the only major stamp absent from the British Royal Family’s private Royal Philatelic Collection.

"Smithsonian National Postal Museum Director Allen Kanes says “you’re not going to find anything rarer than this.”