The letters were written while Jagger, the frontman of the world's most successful rock band was in Australia filming the movie "Ned Kelly" and his relationship with the black American singer was a closely guarded secret.
The collection, which includes song lyrics and a Rolling Stones playlist, is estimated to realise 70,000-100,000 pounds and will be the centrepiece of Sotheby's English Literature and History sale on December 12.
Beguilingly lyrical and displaying a wide range of cultural interests, Jagger's letters, written at a time of great personal and professional turmoil, shed new light on the rock legend.
One letter incorporates the full lyrics for the song 'Monkey Man', rewritten with three additional lines. The collection also includes a track list in Jagger's hand listing nine Rolling Stones songs with brief comments ('OK', 'dodgy', etc).
The letters contain oblique references to the death of Brian Jones and Jagger's increasingly difficult relationship with Marianne Faithfull (with whom he was due to star in "Ned Kelly", but almost immediately on arrival in Australia, Faithfull took an overdose of barbiturates and almost died).
Comments Hunt, "When a serious historian finally examines how and why Britain's boy bands affected international culture and politics, this well-preserved collection of Mick Jagger's hand written letters will be a revelation.
"Written during the summer of '69 from a Tony Richardson film set in the Australian outback, they touch upon the first moon landing, John and Yoko, Christopher Isherwood and the Isle of Wight Festival. They're addressed to me. I was 23, American born, Berkeley educated, and Londonbased... Our delicate love affair remains as much part of his secret history as his concerns over the death of Brian Jones and the suicide attempt of his girlfriend, Marianne Faithfull."
According to Gabriel Heaton, Sotheby's Books Specialist, "These beautifully written and lyrical letters provide a rare glimpse of Jagger that is very different from his public persona: passionate but self-contained, lyrical but with a strong sense of irony."
