Carbon dating early Buddhist texts

ANSTO carbon dating tests of rare manuscripts dubbed the 'Dead Sea Scrolls of Buddhism' have confirmed the priceless texts are from the first and fifth centuries AD and could be the missing link in Buddhist history.

The tests were carried out on two out of three international collections, the Senior and Schøyen collections which are owned by private individuals. The third is owned by The British Library. Results showed that two manuscripts from the Senior collection date between the years 130 and 250 AD and three of the Schøyen texts between the first and fifth century AD.

At ANSTO, Dr Geraldine Jacobsen was in charge of the delicate chemistry needed to prepare the samples for dating. She explained that before analysing the actual scrolls - which were made out of birch bark - a sample chemistry test needed to be conducted.

"As we have never tested birch bark before we needed to ensure we got the chemistry right as sometimes samples don't survive the pre-treatment stage," she said.

"In the treatment, we had to remove any impurities that might have affected the date and as we had no idea how the scrolls were handled or if any conservation attempts were made, we had to use a series of organic solvents, such as hexane, chloroform and methanol to remove grease or resins.

"This process was followed by washing with acid and alkaline solutions which remove other possible contaminants, including the solvents we used in the first step, as these would also affect the dating if they remained."

Another problem Dr Jacobsen faced was the delicate nature of the birch bark which was extremely fragile and might be destroyed during treatments. However, the test sample showed the bark could survive the chemistry so they proceeded to go ahead with the dating process in one of ANSTO's particle accelerators. Accelerator mass spectrometry (AMS) and tests commenced on the scrolls in 2004.

Carbon dating dates the material itself, in this case when the bark grew, not the time the writing took place. However, by dating the bark it gives a very good indication of when the texts were written.