For the first time in the chateau's multi-century history, a limited number of 15-litre Nebuchadnezzar bottles of Yquem will be released to commemorate the 2005 vintage the iconic sweet white wine of Sauternes, southwest France.
"It's an incredible vintage, and we wanted to do something to celebrate," Chateau d'Yquem president Pierre Lurton, an experienced Bordeaux winemaker, told AFP.
"The wine is complex, but not super-powerful. It's sweet but also subtle, fresh and elegant. It's everything we could wish for in this wine."
Lurton worked with London-based wine merchant and broker Bordeaux Wine Investments to develop the offer of 100 "Nebs" at 8625 pounds ($16 900) a bottle. The chateau will keep a further 20 bottles for future use.
In spite of the outsized price tag, the fact that it won't even be bottled until 2009 and that it takes several people to pour a Nebuchadnezzar ? the wine is selling like bullion during wartime.
"We've sold 41 so far," said Robert Lench, Managing Director of Bordeaux Wine Investments, which was allocated 50 bottles. The other 50 went to its US sister company Bordeaux Wine Locators.
"Some have gone to buyers based in the UK, and others to the Far East. We know one or two clients have purchased the wine for investment, but there definitely others who plan to drink it someday."
Chateau d'Yquem's cult status can be attributed to several factors.
Once owned by Eleanor of Aquitaine, the 110-hectare vineyard which the hand-picked Semillon and Sauvignon Blanc grapes come from is acknowledged to be the best-situated in the Sauternes appellation.
Yquem ? famously collected by heads of state including Thomas Jefferson, the third US president ? is made when climactic conditions allow fully-ripened fruit to be shrivelled by the temperamental Botrytis cinarea fungus ? so-called "noble rot".
The result is a small amount of precious, super-sweetened juice. At only 66 000 bottles per vintage, Yquem is produced at a rate of 1/10th that of most other big-name Bordeaux.
In the best years, the convergence of weather, geography, grapes and winemaking technique result in wine that when stored correctly, can last for centuries, making it particularly covetable ? and costly ? though large bottles are in another league altogether.
"There may be a secondary market for these bottles because the ex-Chateau sourcing is impeccable," Serena Sutcliffe, head of the international wine department at Sotheby's auctioneers, told AFP.
"But the market for such large formats is up and down. In reality, a Nebuchadnezzar of sweet wine is not very practical. It's not like champagne, which can be drunk in quantity by a relatively small number of guests.
"You really have to think of an occasion when you would ever have enough people around to serve one. This is why small bottles can sometimes command a premium."
To date, Yquem has only been bottled in 375-millilitre, 750-millilitre, 1.5-litre and three-litre formats ? plus once, in 1982, in six-litre bottles.
Sutcliffe said that wine tends to mature more slowly in larger bottles ? and sweet wines, even more slowly because the sugar acts as a preservative.
"These bottles will make a nice gift for the grandchildren or great-grandchildren of today's buyers," she said.
The Chateau was bought in 1999 by French conglomerate LVHM after a protracted and public legal battle with one member of the Lur Saluces family which had owned it for 219 years.
The luxury goods group is focusing on establishing Yquem as a deluxe brand, with the potential to create obsessive demand among buyers.
Lurton understands this well.
"I've had the good fortune to try several vintages (of Yquem) recently," he said, citing a notable pre-sale tasting of representative wines from a historic 135-bottle collection dating back to 1860, which sold last week for an unprecedented $775 000 dollars.
"I can honestly say that in great years, this wine is orgasmic."