A rare signed proof copy of David Hockney's An Image of Celia, in the original frame and hand painted by the artist, is coming to auction at Bonhams on April 20.

It is the undisputed star item in a sale dedicated to Hockney's work that is sure to attract many art investors.

Dating from the mid-1980s, the Picasso-like image of Hockney's close friend, the textile designer Celia Birtwell, is estimated at between £60,000 - 80,000. It leads a sale which covers the whole spectrum of Hockney's output and techniques from the early Fires of Furious Desire - The Most Beautiful Boy in the World of 1963 (£4,000-6,000) to his Lithograph of Water from the late 1970s (£15,000-20,000).

Textile designer Celia Birtwell as seen by David Hockney

A particularly appealing work is George, Blanche, Celia, Albert and Percy, a photo-collage made up of 68 pictures from 1983, valued at £15,000 - 20,000. Percy is the white cat that appears in one of Hockney's best loved paintings: Mr and Mrs Clark and Percy.

The sale also includes two rarities - an earthenware ceramic cat (£5,000-7,000) from 1955 when Hockney was just 18 and a pencil drawing from the following year, Houses near Eccleshill, Bradford, valued at £4,000-6,000.