An incredibly rare six-litre bottle of 2015 Clonakilla shiraz viognier sold for more than $10,000 at a charity auction on Thursday - but it wasn't the signature by Murrumbateman winemaker Tim Kirk which sent buyers into a frenzy.

The shiraz is still in the barrel and won't be ready for bottling until May next year.

Even though bidders could not sample the drop, an unnamed local businessman splashed out a record $10,200 for the bottle of red.

The unusual charity auction was attended by prominent figures of the Canberra property sector.

Mr Kirk donated the bottle to the Independent Property Group Foundation for the auction.

He said the group's chief officer, John Runko convinced him to carry out this special, one-time bottling.

"We've never bottled a wine in this size before. These [bottles] are so incredibly rare you won't see it ever," Mr Kirk said.

"The 2015 vintage is an exceptional vintage. I think the consensus among the winemakers in this district is that we have never seen a better vintage than 2015.

"With this exceptional vintage, we knew we had the right moment to do it."

Mr Kirk said the cool climate shiraz could be cellared for up to half a century.

"Generally with the shiraz viognier we say you can certainly keep it for 10 years and it'll continue to develop beautifully," he said.

"In a great vintage like 2015 that pushes it out to 20 years at least and in this size, this could be a 50-year proposition really.

"It may be something his grandchildren are enjoying."

Mr Runko, described the bottle as a: "totally unique offering for wine lovers ... unlikely to be repeated."

An ordinary bottle of 2014 shiraz viognier will set you back $90 while a magnum of the 2013 vintage costs $200.

Proceeds from the sale will go to Bosom Buddies, a Canberra charity that supports women diagnosed with breast cancer and their families.

The foundation has donated $200,000 to Canberra charities this year.