A farmer from Ireland has stumbled upon a 10 kilogram treasure — butter estimated to be old enough that it could have been on the plate of Caesar Augustus.

"We reckon it can be anywhere from 2000 to 2,500 years old," Savina Donohoe, curator for the Cavan County Museum tells As It Happens host Carol Off.

The bog butter, which is made from cows milk is also apparently edible.

"Bogs are a highly acidic environment, the bog was used to preserve things. It was like a refrigerator," Donohoe says.

Bog butter is not an unusual discovery in the bogs of Ireland. The acidity of the bog combined with low oxygen and cool temperatures makes it an ideal way of preserving things. (Cavan County Museum )

Donohoe says she's not curious to give the butter a taste "I certainly did not try and I have no intentions of trying it."

Unlike the sour cream that gets pushed to the back of modern day fridges and forgotten, Donohoe thinks this bog butter, which would have been very luxurious, was not forgotten by the people who put it there.

"The butter we found was buried very deep in the ground. We think it was an offering to the gods," says Donohoe.

The bog butter has been sent to the National Museum in Ireland, as is required when significant finds are made, for study and testing. (Cavan County Museum )

Bog butter is a relatively common find in Ireland. In 2013, 45 kilograms of 5,000-year-old bog butter was found in Tullamore, County Offaly, Ireland.

For more on the story of Ireland's bog butter, take a listen to our full interview.