In what could be a history-creating discovery for Karnataka, Carbon-14 dating of samples of about 600 skulls that were unearthed in Annigeri, in Dharwad district, over the last seven months has indicated they are as old as 638 years.

Speaking to Deccan Herald over the phone from Bhubaneswar, Institute of Phsyics (IoP) Prof D P Mohapatra, who conducted the Carbon-14 dating on the skull samples, said the scientific process undertaken in his laboratory “has been able to consistently ascertain” that the skulls are 638 years old, with an error of plus or minus 60 years.

Mohapatra has sent his detailed report, including an analysis of the series of C-14 tests, to the Dharwad deputy commissioner Darpan Jain. The results were achieved over the last two days after initial hiccups when the instrument broke down.

Archaeologists and historians working under the aegis of the Karnataka Department of Archaeology and Museums, who studied the skulls that were discovered lying in neatly laid rows in Annigeri, first in September 2010 and subsequently in February-March 2011, have prepared a separate report which, according to Prof M S Krishnamurthy, will “convincingly solve the puzzle” over the skulls.

“We have clinching evidence to establish our findings,” Krishnamurthy said, adding that the evidence and the historical facts over what might have happened over 600 years ago that resulted in the burial of so many skulls will be made public after a week.

The department and the archaeologists associated with the Annigeri find are keeping their findings a closely guarded secret. But sources familiar with the discovery and the subsequent study said the skulls were buried after people were killed by perpetrators of a savage war either during the Adil Shahi dynasty era, or during the period of the Vijayanagara dynasty.

They sources said that the skulls could also belong to the period of the Kalyani Chalukyas. The evidence that archaeologists and historians have gathered dates back from the 12th century AD to the 1850s and provide clues to periodic wars and the violent past of the territory that is now northern Karnataka.

Initially when the skulls were unearthed—quite accidentally during excavation work for a drainage system—archaeologists suspected that Annigeri was a massacre site.

State Archaeology and Museums Director Prof R Gopal said: “We have several evidence—from the 13th century AD when there was a religious massacre in Annigeri to a date in the 15th century when a unit of the Adil Shahi army killed hundreds of people here.”

Gopal said he would rather wait for the C-14 test results rather than conjecture over what might have happened hundreds of years ago.

Two methods were adopted at the IoP laboratory while performing the C-14 tests. The first one was to extract collagen (these are naturally occuring proteins found as fibrous tissue in bones and catrilages) and the second was a direct ‘assimilation’ of the bone from the skulls. “In both the methods, the result – 638 years – was consistent,” Mohapatra said.

Radio-carbon dating is a fairly accurate and reliable method to obtain age estimates on organic materials. Carbon-14, or radiocarbon, is a radioactive isotope of carbon and its presence in organic materials is the basis of the method.