A letter recovered from the body of a passenger on the Titanic has fetched $166,000 at auction.

The selling price for the document, believed to be one of the last letters written before the ocean liner hit an iceberg and sank in the Atlantic, surpassed expectations.

British auction house Henry Aldridge & Son had predicted the item would go for £60,000 to £80,000 ($79,000 to $106,000). The identity of the buyer, who outbid rivals on Saturday with a £120,000 ($166,000) offer, wasn't disclosed.

The letter was written by first-class passenger and American salesman Alexander Oskar Holverson to his mother. It contains the haunting line "If all goes well we will arrive in New York Wednesday A.M."

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One reason it was so sought after by collectors was because it's dated 13 April, 1912. That's just one day before the ship sank midway through its maiden voyage from Southampton, England, to New York.

The letter features Holverson's personal impressions of the ocean liner, the biggest in the world when it was completed more than 100 years ago.

"This boat is giant in size and fitted up like a palacial hotel," he wrote.

Holverson also describes his awe at seeing fellow first-class passenger John Jacob Astor, at the time one of the world's richest people. Holverson and Astor both died when the ship went down, along with about 1,500 other passengers and crew. Roughly 700 people survived, including Holverson's wife, Mary.

Holverson's body along with the letter and other personal effects were recovered from the Atlantic days later.

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The sale tops the previous record for correspondence sent from Titanic.

In 2014, a letter written by second-class passenger and survivor Esther Hart sold for £119,000 -- also at Henry Aldridge & Son, which specializes in Titanic memorabilia.

That's less than the price Holverson's letter went for in pounds. But the U.K. currency has fallen sharply against the dollar since Britain voted last year to leave the European Union. That means Hart's letter was worth a lot more in dollars when it was sold in 2014 -- about $200,000, according to exchange rates at the time.

Another storied piece of Titanic memorabilia that changed hands at Saturday's auction was an iron locker key from the ship belonging to Sidney Daniels, the last surviving member of the crew. It sold for £76,000 ($100,000).