The natural pressures that develop in mud as it dries create 'premeditated but unpredictable fissures'. The work is called Hard Earth and it is being photographed almost every day to record how the pattern of cracks changes. Like most of Goldsworthy's work, it will survive only in photographic form.
But in that form his work has become enormously popular. He has just had an exhibition at the Edinburgh Festival; his next will be in Australia and New Zealand, followed in 1993 by Japan.
Goldsworthy, a 36-year-old from Dumfries and Galloway, suits the ecological spirit of the age by making art from mud, from carefully chosen leaves pinned together with thorns, from ice, snow and sand. He used to issue colour photographs in very small editions - say between three and seven - and they cost around pounds 2,000 a time. Now he is selling one unique photograph for each art work - a recent pile of kangaroo bones in Australia costs pounds 3,500.
Across the road at Agnew's, you can find the opposite end of the contemporary art spectrum. John Wonnacott, 52, has always done the most unfashionable thing imaginable: paint highly finished, realistic pictures. He is a very good portraitist, and is more fascinated by the texture of skin than the soul. The most attractive pictures in this show are devoted to his family, friends and self-portraits mixed into curious architectural fantasies. They are priced in the pounds 16,000- pounds 25,000 range.
He is also showing some amazingly complex paintings of shipbuilding at the Devonport Royal Dockyard. He was commissioned to paint one picture there by the Imperial War Museum and stopped to paint half a dozen more, dense with mysterious machinery. He is apparently hoping to attract Greek shipowners.
Annely Juda Fine Art in nearby Dering Street is showing the grand old man of Spanish sculpture, Eduardo Chillida, underlining the extraordinary range of art styles in fashion. Chillida is seen in the Old Master class, and so belongs to a different price bracket from the two British artists.
A large piece of bent steel, the style of object that he is best known for, can cost pounds 340,000 - for instance, his Emparantza of 1990, which measures 118 by 30 by 30cm. He is also showing paper works; he has created abstract patterns, partly by cutting the paper and partly by drawing on it in black ink. A large one (80 by 122cm) can cost as much as pounds 34,000. Prints made in the same fashion start at pounds 1,000.