The basalt of the Hebrides has magical origins. Sixty million years ago the plate on which northwestern Europe sits was being torn in two. Along the ragged edge of the break, which stretched from Iceland to the Faroes, down the west coast of Scotland and on into Antrim, Slieve Gullion and the Mountains of Mourne, wild energies were released. Here and there, in the Cuillins of Skye, that deep-earth violence erupted in volcanoes five miles high. But for most of it, the liquid magma, heated from the earth’s core, penetrated the surrounding world far underground, two miles or more beneath the surface. Channels and rivers of hot rock drove their way into the muds and shales and pooled out there, squeezing plugs of half-molten mush into the old body of the earth.

Once these giant rock reservoirs were in place, they began to cool, and as they cooled they shrank. Just as mud on the floor of a drying lake shrinks into a pattern of interlinking octagons and hexagons, the cooling basalt split into huge geometric columns, sometimes bending slightly like a stand of bamboos in the wind, sometimes steeply curved like the mouldings of a demonic palace, sometimes even wavy, like the hair of a gorgon or a Soviet warrior heroine. The basalt’s burning, liquid origins stiffened into columned architecture.

Time passed and the overlying layers were worn away. Since the last Ice Age the great rock forms have been out in the air and exposed to the sea. Of all places in Britain, nowhere is this dramatic history more apparent than in the tiny Shiant Isles, a group of islands in the Minch, north of Skye and east of Lewis. It was here in the summer of 2003 that Jill McManners first encountered the intense and violently sculptural rocks which are the subject of these pictures.

It was an exceptionally powerful meeting of a particular sensibility, at a particular moment, and a particular landscape. In the 1970s she had trained as a sculptor at the Central School of Art and Design and then through the 80s worked at A&A Sculpture Casting, a fine art bronze foundry in the East End, casting artists’ work, scaling it up, making the moulds, building workbenches, in other words becoming deeply involved with the gritty physicality of the whole sculptural process. She had already fallen in love with and been painting in the Hebrides, but with the softer, sandier version of them, the milk-smooth beaches, the flowery sward of the machair, the night-long, midsummer sunsets, the other end of the world from anything which the raw presence of the Shiants would provide.

Then life intervened: marriage, children, running a home, the usual problem of multiple lives. By 2003, those demands were ebbing. McManners and her family were together on a small sandy island in the Sound of Harris where they have a holiday house, and the invitation to visit the Shiants came from a friend with a RIB. The Minch, as it does occasionally in midsummer, had settled into oil-like calm, as still and heavy as the surface of a tin of paint. Nothing prepared the holiday party for the shock of the Shiants.

They seemed to her that day like an eruption which had gone cold but which in its cooling and becoming solid had retained the sense of the violence of its making, of vast, mobile earth-forces which had become frozen here and fixed, as if in an endless rage; and then, overlaying that, all the evidence of life and time, a beautiful, mottled skin of lichen and algae, a crust of life on rocks which look as if they might be the denial of life itself.

That hovering ambiguity in the Shiants, both beautiful and horrible, inviting and deeply alarming, as if you are looking into the heart of things, is what struck Jill McManners that calm summer’s day. The party took their boat right up to cliffs that rose 500 feet above them, touching and breathing in the strange, almost blood-like, iron-rich smell of the rock, feeling themselves outscaled by the uncompromising, sculptural bulk of the place. The Shiants may look small on a map but there is no sense of smallness when you are up against them. Everything they say speaks of another scale of time, power and space. Next to them, if you are listening, you can’t help but feel small yourself.

It was as if McManners’s own life story had led up this moment: the training and physicality of casting bronze, the enforced leaving of all that when children and family called, the unsatisfied appetite for a renewed physical contact with otherness. She could not quite encompass her sensations that day, taking hundreds of photographs, drinking in the ‘monumental, crumbling and weathered states of these forms…

feeling them against my palms, worryingly close. It was the atmosphere of the rock, this almost claustrophobic, overpowering rockiness. I don’t love the Shiants. I didn’t then and I don’t now. They are frightening, like the sea, very wild, with the wildness in them, as if wildness had been shut in here.’

Only once before has an artist of any stature responded to the inherent drama, the locked-in story, of these rocks. In about 1815, William Daniell as part of a long tour of the entire coastline of the British Isles, came to the Shiants and engraved a pair of copper plates from which a pair of acquatints were made. Daniell’s images acknowledge the huge implicit power of the basalt but keeps it at a distance. The cliffs are within a landscape and, although they are enormous, the context is clear. This is nature humanized by boats and birds around them. Things are all right in Daniell’s world. All is still, and the islands brood in his pictures, as if they were large, beneficent and sleeping whales.

William Daniell, Near View of one of the Shiant Isles, London 1819

The very opposite seems to be driving Jill McManners’s images: a desire to make the overwhelming reality of the rocks as powerful in what she paints as it is in truth. There is no holding things at arm’s length here. And that power in her paintings has many nuances and moods. There is the sense, as she has said about the Shiants, that ‘you could cut yourself on this place.’ But it is more than that, because these are not images merely of threat or terror. That is there for sure, in the deep black hollows of the shadowed caves and sea-passages through the rock, what she calls ‘the hidden darkness where it curves in’; in the otherworldly astonishment of the pink of the coralline and the sea-blue-green of the many-fathom-deep water that lies at the foot of the cliffs and even within the caves, colours that seem too much for these islands but, as I can attest, are true to life, or at least to the extreme form of life which these islands nurture. But alongside that unadulterated strength of reality, there is the astonishingly vivid flickering variability of life and colour within the columnar bands, the great beards of shaggy lichen, the moss cushions, the tufts of thrift, the sense that nothing has been generalized here and that the essence of every square inch of these rock faces, their ever changing multiplicity, has impressed itself on the painter’s mind.

I have known these places all my life and I had never imagined that someone else could seem to know them as intimately as I do. But Jill McManners has done that in what seems to me a set of groundbreakingly beautiful paintings, an encounter with the reality of part of the world which most people either ignore or are too alarmed by to acknowledge. She has, of course, moved many miles beyond the picturesque but has not succumbed to any easy abstraction, any denial of the raw realities she saw that summer day.

I also know it has not been an easy road for her to follow. For three years after seeing these rocks, she could not bring herself to paint them. She made many experiments with the right kind of paper (the final answer was an enormously heavy 600g/m2 Italian paper which is left to dry , never pressed or flattened) and with many different forms of opaque and transparent washes, some granulating, others staining the paper, to bring about the mobile, living, serious and life-rich surface of encrusted rock which she has achieved here. Many of the columns have five or six washes on them, a layering of paint which mimics and recreates the layers of life, rock and time.

To me, the most powerful of these images are those which almost entirely leave behind a sense of topography. This is not really about ‘place’ in the neat and comfortable sense of that word. They are about more than that, a recognition of the world’s insistent and irreducible reality. When the picture is so close up against the cliff that it looms over you, almost, strangely, as if ready to punish you, not lying calm and pet-like at your feet, as the islands do in William’s Daniell’s acquatints, that is when the miracle of this encounter between a painter and the natural world is at its most powerful. The pictures have almost become natural phenomena themselves. They are within millimetres of being sculptures and, to me, the measure of their power is this: I have known the Shiants for 40 years but I also know I will never see them in the same light again. It is as if Jill McManners has released something from these rocks which has been shut up in them ever since they were made.