According to British auction house Henry Aldridge & Son, the amount paid by an American buyer exceeded the 100,000 to 150,000 pounds (116,000 to 175,000 euros) estimate published before the sale.
It beat the previous record for a Titanic artifact at auction, which was achieved in 2013 for a violin of £1.1 million, the auction house said.
The violin case sold for £360,000 (€420,000) at a watch auction today.
The watch, engraved with the initials JJA, belonged to American businessman John Jacob Astor, who died in the early hours of April 15, 1912, when the Titanic sank at the age of 47.
Considered one of the richest men in the world at the time, with a fortune of $87 million, the equivalent of several billion today, he died on board after watching his new wife, Madeleine, board a lifeboat.
Among the 1,500 people who perished on the Titanic, American author Jack Futrelle described smoking a cigarette in his final moments with another passenger.
His body was found on April 22, 1912, along with his 14 carat gold pocket watch.
John Jacob Astor's “watch has been fully recovered” worn by John Jacob Astor's son, making it one of the most unique and important pieces in Titanic history, the auction house said.
FP // JMC
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