...so that Taj Mahal get its gleam back

Archaeologists have started giving a facelift to the centuries-old Taj Mahal by applying a mud pack to the marble exteriors of the country's most famous monument. The procedure, expected to cost Rs 28 lacs (70,000 USD), will restore the gleam to the 17th-century architectural wonder, says Vijay Upadhyay

Known as poetry in white marble, the Taj Mahal has been the centre of environmental debates for decades, which have been focused on the apparent 'yellowing' of the monument's white surface. This is due to the reaction of pollutants with marble that have caused a yellow tinge on the monument.

Though the Archaeological Survey of India has refuted the claims of a 'Yellowing Taj', the effect of the polluted air combined with dust-laden winds from Rajasthan blowing over the monument, has actually drilled microscopic 'pits' in the smooth marble surface, which renders a yellow tinge to the Taj Mahal apparent from a distance.

But this yellow tinge is about to get washed away, as for the second time in the past six years, the Taj is undergoing a monumental beauty treatment that includes an 'exfoliating facewash' after the application of a multani (mooltani) mitti (Fullers' Earth) mud pack, an Ayurvedic beautification recipe known to women in India for ages.

Recently, archaeologists in Agra embarked on a six-month project to clean up every nook and corner of the Taj Mahal's pristine white surface, mixing huge quantities of Fullers' Earth in water to make a thick paste that was then painstakingly applied to a part of the western wall of the monument, to be covered immediately with sheets of paper to allow it to dry completely.

Explaining the reason behind the application of a traditional cleaning method when there were a number of chemical cleaning agents available for such purpose, SK Samadhia, chief chemist (archaeology), Agra said: "The quality of marble used in the Taj Mahal is one of the best stones in the world and it has withstood the rigors of over 300 years without a even a blemish on its surface. But on studying the effect of different chemical cleaning agents, the ASI found that such chemical agents had a long-term degrading effect on the structure of marble. The surface may appear clean, it could become brittle over time."

Samadhia said that contrary to popular belief, the Taj, or any form of white marble, could not become yellow with age unless exposed to strong chemicals or left to collect grime and dirt over time. The Taj was also experiencing an identical condition.

Since it's located on the Rajasthan border, Agra is susceptible to strong dust-storms with tons of yellow silica dust during summer, which accumulated on the surface of the monument, only to be washed away by rain, highlighting the need for a specialised cleaning process for the monument.
But here, another factor came into play. Air pollution around Agra caused occasional acid rains over the city which reacted with the marble causing the formation of microscopic pits into the surface of the monument and some of the dust particles raining on the Taj got stuck in these 'pits', ultimately making it appear yellow due to the accumulation of millions of such sand particles on the marble surface.

When applied evenly in the form of a thick slurry, the Fullers' Earth, which is a form of lime-rich clay, seeps into these pits and adheres to the accumulated sand particles. Left overnight, this 'mud pack' is peeled off before it dries completely, resulting in a complete exfoliation of the monument's surface under the pack.

According to Samadhia, there had been doubts raised by some environmentalists that the application of a mud pack could result in uneven white patches on the Taj's surface. But the mud pack is only being applied in select vertical portions of the monument which remained unaffected by rain, being vertical. At any time, only a small part of the monument will be undergoing the treatment, as unobtrusively to the tourists as possible.

Regarding the effect of the Fullers' Earth, which is a natural bleaching agent, on the marble, he said that it was only after elaborate tests conducted by the chemical branch of the ASI, that the decision to apply the mud pack on the monument had been taken. He claimed that this was not the first time when the monument was undergoing a beauty treatment.

In fact, he said, the first trial of a mud pack was six years back on a small portion of the Taj after which, it was observed for three years. The success of this experiment spurred the ASI into applying the mud pack on the entire monument and this is the second time it is being done.
He said that this work, expected to cost Rs 28 lakh, would continue until late March and resume in January next year for another three months, as the mud pack was best effective in the winter months, whereas in summers, it became completely useless, drying too quickly to enable it to adhere to the sand particles clinging to the marble surface.

Interestingly, the restoration of the Taj had been first suggested by Lord Curzon, British Viceroy of India in the early 20th century, which ultimately laid the foundation of the Archaeological Survey of India, but the real efforts towards restoration of the monument's beauty have only begun in the past decade with the Supreme Court of India ordering a shutdown of polluting industries in the region and also placing a number of restrictions on the automobile traffic in Agra, a move which has resulted in a considerable improvement in the quality of air around the Taj.