A postage stamp from 1850, one of the first used in Switzerland, has sold for a record SFr348,000 ($293,000) at the world's largest stamp auction.

Collectors from all over the world have gathered this week in Wil in canton St Gallen for an auction where stamps worth a total of more than SFr15 million are expected to change hands.

A "Rayon I" was worth five centimes when it was issued in Switzerland in the middle of the 19th century, but modern collectors said it is worth SFr150,000 today. The stamp sold on Tuesday for more than double that, a sum deemed "extremely high" by auctioneers Peter Rapp.

Featuring a horn above a red shield bearing the white Swiss cross, the Rayon I was one of the first countrywide stamps to be put into circulation after cantons adopted the federal constitution in 1848.

Other stamps are expected to fetch large sums at the auction, which lasts until Thursday.

Among those are several "Basel Dove" stamps, the only kind ever issued by that canton. Originally worth 2.5 centimes when issued in 1845, the stamp is now worth more than SFr100,000, collectors say.

In compliance with the JTI standards

More: SWI swissinfo.ch certified by the Journalism Trust Initiative