The U.S. Library of Congress says it has uncovered long-forgotten recordings by some of the superstars of American jazz -Thelonious Monk, John Coltrane, Ray Charles and the Dizzy Gillespie Orchestra.

Recorded in 1957, the tapes have never before been heard in the United States. The Voice of America recorded the music at a Carnegie Hall concert in New York City for broadcast to the rest of the world.

A jazz specialist at the library Larry Appelbaum says discovery of the tapes is an event of major significance for musical scholars and historians.

Along with introductions by VOA's legendary jazz program host Willis Conover, the recordings feature nearly an hour of live performances by pianist Monk and his quartet together with saxophonist Coltrane.

The Library of Congress has made high-resolution digital copies of the tapes available to researchers, and reportedly is considering releasing the music commercially. The tapes also include performances by Sonny Rollins and the Zoot Sims Quartet with Chet Baker.

The library's collection of recorded music, the largest in this country, includes more than 50,000 VOA recordings from 1946 to 1988.