A prop central to the celebrated opening scene of Citizen Kane – widely regarded as one of the best films ever made – has sold at auction for $14.75m (£11m).

The wooden Rosebud sled, one of at least three known to have survived, was long thought to have been lost until it was given to director Joe Dante in 1984, saving it from destruction.

He went on to use it as a reference for fans (known as an Easter egg) in films he directed, including Gremlins 2: The New Batch.

It is now the second most expensive piece of memorabilia to have ever been sold – a pair of ruby slippers used in The Wizard of Oz sold for $32m (£23.9) in December.

“Along with Dorothy’s ruby slippers, the Rosebud sled from Citizen Kane is one of the most iconic objects in Hollywood history,” Joe Maddalena, executive vice president at Heritage Auctions, which held the action, told its magazine the Intelligent Collector.

The identity of the sled’s buyer was not revealed.

Other Rosebuds made for the film have been sold in the past, including one to legendary director Steven Spielberg, who later donated it to the Academy Museum of Motion Pictures in Los Angeles.

However, the version sold on Thursday had not been seen for many years until it ended up in the hands of Dante.

He told Heritage auctions how he was making the film Explorers in 1984 on the same studio that was formerly owned by RKO Radio Pictures, which produced Citizen Kane.

Dante said crews were on site clearing out storage areas when one worker, who knew he liked vintage films, asked if he wanted it.

“I was astonished…Since I am a huge fan of the movie, I said, ‘Yeah, I’ll be glad to take it.”

“Citizen Kane may be the greatest film ever made, and Rosebud is the linchpin of the story – the whole heart of the plot and the focal point of the mysterious drama in Kane’s life.

“As a director, to own the prop that represents such a vital element of a cinema treasure is particularly meaningful.”