Mauritius "Post Office" stamps

For many collectors these are the summit of the hobby. In 1847 Mauritius issued a one penny orange-red and a two pence deep blue, engraved locally on a small copper plate by Joseph Osmond Barnard. They read "Post Office" where the later issues say "Post Paid," and only 240 of the first printing were sold before the change. Lady Gomm, the governor's wife, used some on invitations to her costume ball of September 30, 1847, and that envelope is in the British Royal Collection. Around thirty copies of the two stamps are thought to exist. The Bordeaux cover, the one envelope known to carry both values, sold at auction in 1993 for 6,123,750 Swiss francs.