Of innocence and experience

Rachel Whiteread is a major sculptor, and now she has her first major retrospective - at the Tate Liverpool

Rachael Whitbread's short career has been a success story and her exhibition at the Liverpool Tate Gallery demonstrates that there are good reasons for her reputation. It's only a decade since she left art school (at Brighton and the Slade) and now she has a major international role as the sculptor chosen to make a monument in Vienna to the thousands of Austrian Jews killed by the Nazis. Whiteread was one of 10 artists invited to submit proposals for this memorial sculpture. The awesome nature of the project would have unnerved anyone, however thoughtful and mature. Well, it appears that Whiteread has devised a work that is appropriate to the theme, and even without seeing the completed work we can be pretty sure that it's an achievement.

It's also remarkable that the monument (to be unveiled on 9 November) is completely within the terms of Whiteread's art. If there are resemblances to other memorials they are coincidental. One has the impression of a person who was born to make sombre and moving commemorative structures. When looking at the work in Liverpool, which goes back to 1988, one does not have the impression of a young artist. Indeed it is hard to imagine that Whiteread ever had the impulses one associates with youth. Her work is uneven in quality and effect, as is natural in the first decade of any artist's life. But the sculptures do not have the vivacity or the openness to influence that we usually find in creative people when they are starting their careers. At their best they are lonely and mournful; and though they have the imprint of human experience they seem to have come from nowhere.

This is because of the strange nature of Whiteread's procedures. Characteristically, she casts space. The sculptures are solid and tangible. But their actual physical form is that of a space that previously had no form, being only the emptiness between objects, or between walls, or between the sides of containers. The discovery of this solidification of space, which has no real precedent in art, came when Whiteread made Closet in 1988. She justifiably describes this piece as her breakthrough. Factually, it is the inside of a wardrobe, for it was cast inside a real wardrobe that was then pulled away from the plaster and discarded. Emotionally, Whiteread found that she had made an object that gave physical form to childhood experiences in her grandparents' home, and the more recent and transient experiences of living as a student in a number of bedsitters.

Wishing to intensify feelings of claustrophobia, Whiteread covered the plaster with black felt. This gives the piece a dark and even menacing note. On the other hand, the added material makes the sculpture reminiscent of other works of art. In later pieces the plaster is, as it were, naked. Simple plaster helps make Whiteread's objects more ghostly and anonymous, as at one time appeared to be her aim. And yet these cupboards, sinks, baths and beds always had the traces of habitation and use. So the anonymity began to feel as though one could almost be in touch with people who once had been present and active. This, of course, is the function of a monument. And thus Whiteread quickly progressed from thinking about her childhood to considering the longer marches of destiny.

A plaster sculpture like Bath inevitably puts one in mind of a tomb or a coffin. Perhaps when it was first made it looked too ancient, for Whiteread then added a sheet of glass. The glass contrasts modern with old a little uneasily to my eye.

Whiteread's art has a long future, and some day it may turn out that in her early years she failed to find the perfect material for her expression. In Liverpool we meet rubber, fibreglass, polystyrene and resin. To manufacture objects from such material is natural in an artist born in 1963. And a further new material may well be invented that suits Whiteread's purposes - whatever they may be in the next century. This said, I find the Table and Chair, made in clear hard rubber, a satisfying work, maybe because it is so architectural.

New materials inevitably bring the problems of texture, colour and transparency. Many of the sculptures are half-transparent or have a shininess that suggests that they might be transparent. I guess that this area needs a lot more exploration. The question of colour may not be soluble. Whiteread has a lot of colour effects, but they remain effects. Like an apprentice watercolourist, she has no palette. There's a knack for merging tints but not a positive use of hue. The Amber Mattress works because it is a single colour and it has been carefully lit. Whiteread has made an attempt at various colour in her One Hundred Spaces. Here are 100 resin casts of the spaces under chairs, arranged symmetrically. Though it's the largest work in the show it lacks power.

As we know, no sculptor in modern art has ever fully overcome the difficulties presented by colour in three-dimensional work. I don't see that Whiteread will succeed where so many others have failed. The exhibition catalogue prints interesting pieces by Stuart Morgan and by the show's curator, Fiona Bradley (whose writing is the most promising by any current art administrator). On the whole they take a phenomenological approach to Whiteread. They see her work as peculiar and individual. So it has been. My own hope is that Whiteread will become imaginatively concerned with future architecture. In Liverpool there's a sort of plaster sketch of the Judenplatz memorial and a maquette of the future monument. The plan has been of a concrete cast of a Jewish library, turned inside-out so that the spines of the literary culture of the "people of the Book" face towards the world. A lovely and dignified idea. Construction is behind schedule, but the IoS will feature a photograph of the memorial sculpture as soon as possible.

! Tate Gallery Liverpool (0151 709 3223), to 3 Nov.