The Mauritius Post office (Best known Stamp)

The rarest postage stamps in the world, and are of legendary status in the world of philately. Two stamps were issued, an orange-red one penny (1d) and a deep blue two pence (2d).The stamps, as well as the subsequent issues, are highly prized by collectors because of their rarity, their early dates and their primitive character as local products. Surviving stamps are mainly in the hands of private collectors but some are on public display in the British Library in London, including the envelope of an original invitation to the Governor's ball complete with stamp. Another place where they can be seen is at the Blue Penny Museum in Mauritius. The two stamps also can be seen at the Museum for Communication (Museum für Kommunikation) in Berlin and in the Postal Museum of Sweden in Stockholm.

The Mauritius "Post Office" stamps were unknown to the philatelic world until 1864 when Mme. Borchard, the wife of a Bordeaux merchant, found copies of the one and two pence stamps in her husband's correspondence. She traded them to another collector. Through a series of sales, the stamps ultimately were acquired by the famous collector Ferrary, and were sold in auction in 1921.
Over the years, the stamps became legendary in the philatelic world and sold for increasing and ultimately astronomical prices. Mauritius "Post Office" stamps and covers have been prize items in collections of famous stamp collectors, including Arthur Hind, Alfred F. Lichtenstein, and Alfred H. Caspary, among other philatelic luminaries. The greatest of all Mauritius collections, that of Hiroyuki Kanai, included unused copies of both the One Penny and Two Pence "Post Office" stamps, the "Bordeaux" cover with both the one penny and two pence stamps which has been called "la pièce de résistance de toute la philatélie" or "the greatest item in all philately", and numerous reconstructed sheets of the subsequent issues. Kanai’s collection was sold by the auctioneer David Feldman in 1993, the Bordeaux cover going for the equivalent of about $4 million