Most of the feature-length films made by Hollywood during the golden age of silent movies have been lost forever, according to a new study by the US Library of Congress.

Only 14% of a total of around 11,000 movies made between 1912 and 1930 exist in their original format, with a further 11% available to view in foreign language versions, or in a lower quality format. Around 70% are completely lost. The failure of the early studios, in most cases, to maintain silent era archives has been described as an "alarming and irretrievable loss" to America's cultural record by officials.

Historian and archivist David Pierce, who conducted the extensive two-year study, said the silent art form retained a rare resonance. "It's a lost style of storytelling, and the best of the films are as effective with audiences today as they were when they were initially released," he told ABC News. "When you take away dialogue from a narrative story, it actually puts quite a challenge upon the creative people involved to tell the story entirely in a visual fashion. And it's that limitation, I think, which makes the films so effective."

Many of the lost film prints fell victim to fire or deterioration. Others were neglected or destroyed, according to the common practices of the time. Of the major studios of the era, only MGM kept a decent library of silent fare, with early 20th century giant Paramount considered one of the most neglectful. The latter did not begin preserving titles until the 1980s and has reportedly lost more than two-thirds of its once huge library of more than 1,000 silent films.

Famous titles now considered lost forever include the 1917 version of Cleopatra, a 1926 take on F Scott Fitzgerald's much-adapted The Great Gatsby, Lon Chaney's 1927 film London After Midnight and 1928's The Patriot. The library's next aim is to contact foreign preservation groups and private collectors in the hope that some of the missing examples can be tracked down.

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