The world's first airmail envelope, which piqued the interest of the French president, has been sold by a New Zealand dealer for almost $250,000.

The 140-year-old stamped envelope, mailed from France to Australia, was auctioned in Sydney this week by an Otaki dealer. It was originally valued at $61,732, but fetched a record-breaking $238,625.

In a daring bid to deliver the world's first airmail, letters were taken out of Paris by hot air balloon as the city was besieged during the Franco-Prussian War of 1870-1871. They were then delivered by sea.

The history behind the 1870 Siege of Paris Balloon Post Cover captured the attention of France's President Nicolas Sarkozy, who requested an auction list.

The collectable was bought by a French dealer, who flew in for the auction. The price was a record for any philatelic item sold in Australia or New Zealand.

Mowbray Collectables sold the envelope on behalf of an Australian, who had owned it for 20 to 30 years.

Managing director John Mowbray said: "This envelope is an example of the world's first airmail, and only one Paris Balloon Post Cover addressed to Australia is known."

He said the price fetched was not a surprise given the item's rarity and the fact that stamps were drawing very good prices.

Meanwhile, police are investigating the theft of an $80,000 stamp collection from Lower Hutt's Horticultural Hall on Sunday.

During an event at the hall, owner Bill Leggett turned his back for a few seconds then found his prized collection had been stolen. No arrests have yet been made.

Source: stuff.co.nz