By JOHN F. BURNS New York Times

AILSA CRAIG, SCOTLAND

This stunning volcanic island has been part of Scottish legend for a thousand years, its sugarloaf profile decorating Scottish bank notes and memorialized in a Keats sonnet.

It has no inhabitants, no electricity, no fresh water and no arable land — nothing of value, it would seem, but for this: For a century and more, its quarries have been the source of the distinctive, water-resistant microgranite used to make most of the world's curling stones. These include all those used in recent world championships and every Olympics since 1924, including the Sochi Games that begin in February.

But the modest income from the quarrying of the island's prized strains of blue hone and common green and a lease granted to Britain's Royal Society for the Protection of Birds has taxed the dwindling resources of its owner, the eighth Marquess of Ailsa, whose family has owned the island for 500 years.

Like many of Britain's old landowning families, the marquess's family has been through decades of retrenchment as a result of inheritance taxes. It lost the family seat, Culzean Castle, to the National Trust in 1945, and in 2010 the current marquess decided to part with Ailsa Craig, posting an initial price of $4 million. That figure was later cut to $2.4 million, and as the waters of the Firth of Clyde have lapped at Ailsa Craig's rocky shore each day, little has changed in the intervening years. The island remains misty, monumental and for sale.

When Keats first saw the island soaring 1,100 feet into the sky off Scotland's west coast in 1818, he repaired to a mainland inn and wrote a sonnet by candlelight describing it as a "craggy ocean-pyramid," summoned from the deep by some mythic power, and attended for eternity by eagles and whales. Nearly 200 years later, with Scotland approaching a referendum on independence from Britain in September, it remains an icon in the country's national consciousness, redolent of the rugged, stand-alone character many Scots pride as their birthright.

This month, approaching across 10 miles of shimmering open sea aboard his 35-foot lobster boat, the M.V. Glorious, the skipper, Mark McCrindle, broke the silence of his cramped wheelhouse to say that in 30 years of plying the waters from the nearby port of Girvan, he had rarely seen it looking more majestic. "Aye," he said, "she's a beauty." Would he like to own it? "Twenty thousand pounds is all I'd pay," he said, quickly adding, "What would I do with it?"

Finding a buyer will require more than the poetic flights of Keats, or "the dreams" the 57-year-old marquess says he would be selling to anyone whose fancy runs to an island that has no modern conveniences, no active forms of employment since the quarrying ended in 1969, and only one habitable structure among the rusting, roofless ruins of the quarters once used by men working in the lighthouse or the quarries.

Over the centuries, the island's 220 acres, much of it in the form of precipitous crags and thick uphill reaches of bracken, have provided Scots, and sometimes their enemies, with an ocean fortress. Barely three-quarters of a mile from tip to tip, the island has served as a redoubt for repelling Spanish invaders, a sanctuary for pirates and, for the last 25 years, a preservation area for tens of thousands of breeding seabirds, especially gannets and puffins.

So it is little surprise to find that property agents listing it reach for hyperbole in stating its attractions. "The only island to win a gold medal in the Olympic Games!" says Farhad Vladi of the Hamburg-based company Vladi Private Islands. He claims to have sold more than 2,000 islands across the globe, many of them in more enticing, or at least warmer, locations than the Firth of Clyde.

Vladi's medal reference referred to the curling stones used when Rhona Martin, the Scottish champion who threw what became known as the "stone of destiny" to win the women's gold medal at the Winter Games in Salt Lake City in 2002. The victory set off fireworks celebrations in Edinburgh and Glasgow; it was the first time Britain had won a winter gold in 18 years.

Scots, and others across Britain, are hoping for a repeat at the Sochi Olympics, and they look to Ailsa Craig, at least metaphorically, as a talisman. Two thousand tons of previously quarried granite was taken off the island this summer by landing craft and used for cutting, spinning and polishing into the Sochi stones at the factory at Mauchline, 25 miles away on the Ayrshire mainland, that has a contract for the Olympic stones.

A few of those stones will slip gently out of the sure hands of Britain's best medal hope, its world champion women's team and its 23-year-old skip, Eve Muirhead.