Holding the fort

Phillip King is the one who got away. A sculptor who first hit the headlines in the 1960s, he was as famous then as his decade-older contemporary Anthony Caro. King was one of the first sculptors to use such materials as fibreglass, resin and plastic, from which he made his distinctively coloured cone sculptures - particularly Rosebud (1962) and Genghis Khan (1963). These abstract works were rooted in organic form; Genghis Khan, for instance, looks more like a mountain-top with passing clouds. These sculptures seemed to come from nowhere. There was no precedent for them. They might have sprung complete and fully-armed from Phillip King's mind, as Athene, the Greek goddess of war, did from the head of Zeus.

This is what true sculpture is about: the creation of new form. Few achieve it, though many are good at reinterpreting past ideas or putting a gloss on another's discoveries. With the plastic sculptures of the 1960s, King made something new, unexpected and satisfying, which expressed the age but which also succeeded in being timeless. Consequently, he went on to represent Britain at the Venice Biennale of 1968. Many see that as the high-point of his career, but what has happened since? While Anthony Caro has gone from one pinnacle of fame to another, Phillip King has been somehow sidelined. Although he has spent the past 30 years constantly re-inventing his art, experimenting with new materials and subjects, King has not enjoyed a high public profile. For an artist who has significantly enlarged the boundaries of sculpture, this must be galling, to say the least.

Part of the problem is that in recent years King has had no gallery to represent his interests. This has now been remedied, and the Bernard Jacobson Gallery in London will be showing King's work commercially, with a big show planned for next year. Although there was an important exhibition of King's sculptures at the Yorkshire Sculpture Park in 1992, it speaks volumes that the current retrospective of his work, which he himself sees as the greatest challenge of his career, should be in Italy not England.

It's 25 years since a British sculptor held a solo exhibition at the Forte di Belvedere in Florence. In 1972 it was Henry Moore, for whom King worked briefly as an assistant in the late 1950s. Now we have the chance to assess King's output from a representative selection of all periods of his work. It is a good installation, the sculptures well spaced and placed, both inside and out. The venue is one of many levels, of different rooms and terraces. Several individual sculptures are effectively framed by door,or archway, particularly Slant (1966), a piece composed of brilliant red angled blades, seen against the green Tuscan hills. Round and about are dotted powerful slate and steel pieces from the 1970s.

The exhibition is a visual feast: remark the amazing presence of Blue Blaze (1967), all saturated colour and odd diagonals, placed next to the cool, mysterious, sexy form of Untitled III (1961). Through (1965) explores the red interior of the cone, its flesh so to speak, as if sliced by a wire egg slicer. The juxtaposition of sculpture from different periods serves to emphasize the continuity of King's concerns. For example, the surreal plaster Bird Woman from 1956 sits well with a group of complex bronze maquettes from the 1980s and 1990s. The gentle carapace of Ubu's Camel (1989) is next to a cabinet of 1950s bronze and clay figures. They raise echoes and resonances in each other, enhancing our enjoyment and understanding.

Recently, King has embarked on a series of ceramic vessels, ritual pots, which, though pierced and oddly shaped, can hold liquid. With these works, King has returned to a clarity of form reminiscent of the early cone sculptures. Some are painted (the blue and brown glazes of Head, 1996, make it look rather impressive), but the plainer, biscuity ones are the strongest. The newest work in the show is a group of three lightweight colour pieces; fun and jazzy polystyrene blocks that the artist seems to have nibbled at. These, when taken with the large new piece situated outside, give an indication of how things might progress. The outside work, also cut from polystyrene though coated with concrete paint to preserve it, is called Watching Green. Imagine a waisted jar, a cone, a spiral and various girders and slopes pulled together. It's painted in orange, blueish purple and lime green, and is too luminous for outdoors, where it risks looking like something from an adventure playground. It's an indoors piece, preferably sited in a white room, also incidentally the best setting for the early plastic pieces.

The Forte is a wonderful venue, but it is not ideal for all of King's sculptures. Sons of the big painted steel pieces, such as Quill (1971) and Ascona (1972) look tremendous in the strong light. Slate, however, loses some of its murky allure in this dryness: it needs a wetter atmosphere and a softer light to be shown to best advantage. The main resource of this hilltop site outside the city is that the sculptures can be seen from so many different angles and viewpoints. Not only within the Forte: King assured me that you can see 17 of them from the dome of Florence's Santa Maria del Fiore cathedral. In this big show, full of important pieces, a major sculptor of extraordinary diversity and richness is at last accorded the kind of recognition he deserves.

Phillip King at the Forte di Belvedere, Via San Leonardo, Florence, is open every day except Tuesdays from 10 am till 7 pm, to 30 Sept