A copy of the first installment in J.K. Rowling's hugely successful series, Harry Potter and the Philosopher's Stone, is expected to fetch up to $9,600 (£6,000) at the sale in London next week (beg06Apr15).

Other signed Harry Potter novels are expected to sell from $320 (£200).

A personal horoscope the author penned for a friend is also among lots at the auction and is predicted to fetch $16,000 (£10,000).

Bosses at Bloomsbury auction house, which is holding the sale, write, "This horoscope was written whilst the author was working on Harry Potter and the Philosopher's Stone, and throughout echoes the wry humour and fanciful wit so associated with the author, but combined with a surprising depth of knowledge of the art and history of Astrology."

The Harry Potter series was developed into eight blockbuster movies starring Daniel Radcliffe, Emma Watson and Rupert Grint.