All that glitters is not gold: A non-destructive probing of Thanjavur painting by Raman spectroscopy.

In this work, we demonstrate the use of Raman spectroscopy in detecting the presence of gold and semi-precious/precious gemstones in one of the classical paintings of India namely the Thanjavur paintings which have been awarded the Geographical Indication. We find through Raman spectroscopy that there are paintings where fake gold is used in the place of original gold foils. This result has been validated by carrying out the energy dispersive X-ray analysis (EDX) which confirms the Raman spectroscopy findings. We propose Raman spectroscopy as a diagnostic tool for detecting the presence of gold and thereby to frame regulations for the Thanjavur painting market which would be of utmost importance to the artisans as well as its connoisseurs.