The archive was passed down by descent to the present owner. It contains over 700 letters and postcards, predominantly comprising autograph letters to Helen Anrep, who was the long-term partner of the art critic Roger Fry and a confidante for various members of the group.
Gorringes expect the correspondence, which will be sold as one lot, to realise £50,000-80,000.
Anrep (née Maitland) married the Russian artist Boris Anrep in 1918 and became involved with the Bloomsbury circle in 1924. She met Fry at a party at Vanessa Bell's studio and afterwards left her husband to live with Fry until his death in 1934.
Although not an intellectual or artist herself, she had a keen interest in the arts, provided critical support for Fry's work and was painted by Duncan Grant at Charleston.
The correspondence contains personal letters to and from Vanessa Bell, Roger Fry, Augustus John and Virginia Woolf amongst others, providing an intriguing insight into the complex web of relationships within the group.
The correspondence, covering the period 1907-1947, but chiefly 1919-1947, ranges from the influence that Helen exerted over Fry's work and the effect of world events on the group, to the deepest personal relationships and simple domestic arrangements.
One of the more poignant notes was written by Bell shortly after the death of her son Julian in the Spanish Civil War in 1924, in which she writes: "Helen dearest. In case you hear - Julian died from wounds a few days ago. V."
The 14 artworks from the same estate will be sold as individual lots and include pieces by Roger Fry and Vanessa Bell as well as paintings attributed to Henry Lamb and Duncan Grant.
There is also a plaster figure, La Mediterranee by Aristide Maillol (estimate £4000-6000), which is mentioned in one of Vanessa Bell's letters to Helen Anrep. As Fry was a devotee of Maillol, it likely comes from his collection.
By Anna Brady