India: Study Shows Hemp Has Shielded Ellora Caves From Decay For 1,500 Years
By Steve Elliott
Archaeologists say they've discovered the reason India's famous Ellora Caves haven't decayed over the 1,500 years they've existed. The reason is hemp.
"The use of hemp helped the caves and most of the paintings remain intact at the 6th century Unesco World Heritage site," according to a study conducted by Manager Rajdeo Singh, a former archaeological chemist of the Archaeological Survey of India's science branch, and M M Sardesai, who teaches botany at Dr Babasaheb Ambedkar Marathwada University. The study was published in the March 10 issue of the journal Current Science.
"Cannabis sativa, popularly known as ganja or bhang, was found mixed in the clay and lime plaster at Ellora," Singh writes in the study. "This was confirmed by technologies such as scanning of the electron microscope, Fourier transform, infra-red spectroscopy and stereo-microscopic studies.
"Hemp samples were collected from areas in Jalna district near Aurangabad and also from the outskirts of Delhi," Singh wrote. "These specimens were matched with the samples found in cave number 12 of Ellora. There was no disparity. In the sample collected from the Ellora cave, we found 10 percent share of cannabis sativa in the mix of mud or clay plaster. This is the reason why no insect activity is found at Ellora," Singh wrote in his study.
The study shows that many of hemp's valuable properties were known to Indians in the 6th Century. "Hemp was extensively used in Ellora as well as by the Yadavas, who built the Deogiri (Daulatabad) for in the 12th Century," Singh told Syed Rizwanullah of The Times of India.
"Hemp was not used in the Ajanta caves, which are about 30 rock-cut Buddhist structures dating back to the 2nd century BC," Singh told The Times of India. Rampant insect activity has damaged at least 25 percent of the paintings at Ajanta."
The archaeologist said the outcome of his study was "a discovery in itself."
"Studies in Europe suggested that buildings constructed with the use of cannabis sativa could last for 600 to 800 years," Singh said. "Ellora has proved that only 10 percent of cannabis mixed with clay or lime in the plaster could last for over 1,500 years."
Photo of Ellora Caves: Wikipedia