Indian archaeologists have discovered that hemp – a mix of hemp with clay and lime plaster – has prevented the famous ancient Ellora caves from degrading over the 1,500 years they have been in existence.
“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 new study conducted by archaeologist Rajdeo Singh (ASI) and botanist MM Desai at Dr Babasaheb Ambedkar Marathwada University, Maharashtra, India.
Ellora Kailashnath Temple. Photo credits: InfoTemples
Using two techniques such as Fourier transform, infra-red spectroscopy and stereo-microscopic studies, researchers were able to conclude that hemp, commonly known as ganja or bhang, had helped in preventing insect activity at Ellora.
The study indicates that many valuable properties of hemp 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) fort in the 12th century. Hemp was not used in the Ajanta caves, which are about 30 rock-cut Buddhist structures dating back to the 2nd century BC. Rampant insect activity has damaged at least 25% of the paintings at Ajanta,” Singh told TOI.
Hemp was not used in the Ajanta caves, which are about 30 rock-cut Buddhist structures dating back to the 2nd century BC. Rampant insect activity has damaged at least 25% of the paintings at Ajanta. Photo credits: Discover India
The archaeologist, who has been engaged in the chemical treatment and conservation of ancient paintings at Ajanta for about 11 years, said the outcome of the study was “a discovery in itself”.
“Studies conducted in Europe suggested that buildings constructed with the use of cannabis sativa could last for 600 to 800 years. Ellora has proved that only 10% of cannabis mixed with clay or lime in the plaster could last for over 1,500 years,” he said.
However, there is a problem because the use of cannabis cultivation, transport, possession and consumption of marijuana is banned under Indian law.
Experts say that the existing Narcotic Drugs and Psychotropic Substances Act will have to be amended before hemp can be used on a large scale for construction. For now, “anybody found with the substance will face action.”