Mauritius Post Office Stamps

The British Colony Mauritius produced "Post Office" stamps in September 1847, in two denominations: an orange-red one penny (1d) and a deep blue two pence (2d). Their name stems from the words "Post Office" on the stamps, which was quickly altered to "Post Paid" in the next issue. Only 27 are known to still exist, and they are one of the most famous and sought-after stamps in the world of philately. They are also among the world's most expensive rare postal stamps.

The philatelic world was unaware of the Mauritius "Post Office" stamps until 1864, when Mme. Borchard, the wife of a Bordeaux businessman, discovered reproductions of the one penny and two pence stamps in her husband's correspondence. She sold them to a different collector. The stamps were eventually acquired by the famous collector Philipp von Ferrary through a series of auctions and sold at auction in 1921.

Price: $3.8 million for a pair