Provenance study: Neutron activation analysis to pinpoint geographical origin of archaeological objects

2011
By Syed Akbar
Visakhapatnam, Feb 23: A city nuclear scientist has developed technology to pinpoint the geographical source of archaeological artefacts without damaging their structure.
“So far we have technology to tell the age of an archaeological finding. But now we can tell from which place a particular archaeological artefact has originated, without subjecting the material to destruction,” says senior nuclear physicist Dr N Lakshmana Das.
In conventional technology, archaeological artefacts are subjected to damage and destruction as it involves chemical studies. The new provenance study conducted by Dr Lakshmana Das in association with the Bhabha Atomic Research Centre does not involve any damage to the artefacts like historical potteries, idols, bricks, stones, coins and paints.
“Since they are of great historical and archaeological value, we cannot damage them. They are meant for preservation for posterity. We use instrumental neutron activation analysis to find out the source of the object. So far we have completed studies on 20 Buddhist historic sites and work is in place in another 20 sites covering Bavikonda, Thotlakonda and Pavaralakonda Buddhist locations,” Dr Lakshman Das, who is also the principal of GITAM deemed university.
The artefact, whose source of origin is to be studied, is kept in a nuclear reactor which studies its elementary composition including rare earth elements and gives the analysis quite accurately. “The technology is so accurate that there’s no scope for error. Even if the element is present as minutely as one in a billion parts, the instrumental neutron activation analysis pinpoints to the source material,” he said.
The variation of trace elements depends on the place and preparation and hence determination of concentration of trace elements of significance becomes more important. Group of elements used for provenance studies are alkali and alkaline elements, transition elements and rare earth elements.
As many as 140 Buddhist sites have been identified in Andhra Pradesh ranging in date from pre-Ashoka (3rd century BC) to Vishnukundin times (5th century CE). The sites extend from Dantapuram in the north to Nandaluru in the south and Kotilingala in the west to Bhattiprolu in the east of Andhra Pradesh. Buddhist monks traveled to Sri Lanka via Orissa and Andhra Pradesh and then spread to East Asia. The provenance studies will provide an insight whether the luggage carried by the monks were local in origin.