Excavations in Manchester is being sold for an undisclosed price by the MacConnal-Mason Gallery, whose director Simon Carter said: "It shows Lowry at the very peak of his early years. This is a real museum quality piece. It is the most significant Lowry that we have ever had. It is without doubt the most important picture in the fair."

It is being exhibited beside another Lowry painting, The Old Shot Tower, showing the building where lead shot was made beside the River Tyne in Newcastle by dropping molten lead into water.

"Both pictures come from the same private collection and have not been on the market for some years, " Mr Carter said. "Excavations in Manchester is the sort of thing that usually would come up for sale and go straight into a private collection, so it is nice to be able to bring it here."

Diamond earrings worn by supermodel Kate Moss at the opening of the new Topshop on New York's Broadway early this year are adding sparkle to the fair, which opens in the Harrogate International Centre at 2pm today.

The earrings, which are for sale for £28,000 were loaned to Topshop boss Sir Philip Green by one of his friends, Gerald Licht, and were worn in New York by model Moss with a £174 flowing green evening dress and a black leather jacket. Mr Licht, of the fine art deco and period jewellery company Licht and Morrison, of Mayfair, has the 1920s earrings, shaped like an Aztec pagoda, for sale on his stand alongside a £46,000 Japanese influenced diamond, emerald and onyx bracelet with a rising sun symbol.

Although Picasso is more normally associated with his paintings, an example of his ceramic design – a 13inch tall jug called A Woman's Face, number 22 of a limited edition of 200, made at the Madoura Pottery in Vallauris, France in 1953, is being sold for in excess of £12,000 by Sylvia Powell Decorative Arts.

The fair is open today until 9pm. It is open from 11am to 6pm tomorrow and Sunday, from 11am to 8pm on Monday and 11am to 5pm on Tuesday.