Carla Bruni may have seen a few mudpacks in her time, but nothing on the scale of what she will find when she visits the Taj Mahal this week.

Indian experts have begun a six-month project to clean the white marble archways, carvings and crannies of the world's greatest monument to love by coating them in a special mud.

The monumental face pack consists of multani mitti, or fuller's earth, a lime-rich clay found across northern India and used in many face masks and Ayurvedic body treatments.

K.S. Rana, director of the science department of the Archaeological Survey of India (ASI), told The Times: “We will leave it overnight and then, the moment it starts drying, we will remove it, just like a face pack.

“The marble of the Taj Mahal is quite intact — it is very high quality. There is just some yellowing in the arched areas and other parts not exposed to the rain. The mud is being used to clean only those areas.”

The Taj complex was completed in 1653 by Shah Jahan, the Mogul emperor, in memory of Mumtaz Mahal, his second wife. It is India's top tourist site, attracting three million visitors every year.

Rising levels of dust and industrial pollutants from the surrounding city of Agra, 130 miles (210km) southeast of Delhi, have stained some of its white marble surfaces yellow.

Lord Curzon, the British Viceroy of India, first suggested restoring the Taj in the early 20th century, but serious efforts began only in 1996 when the Supreme Court closed thousands of factories around it.

Motor vehicles were also banned from near the monument, forcing visitors to take rickshaws, electric buses or horse-drawn carriages for the last mile and a half.

The mud treatment, which costs about £115,000 a time, was first tried six years ago and last used three years ago, according to the ASI.

Some experts argue that the mud causes variations in the marble's whiteness and exposes it to fungus and even worse staining, but the ASI says that it is the only way to clean it without causing serious damage.

This year local authorities began a simultaneous campaign to clean up the surroundings of the Taj by demolishing illegal structures, banning squatting and restricting rickshaws to designated areas.

Dr Rana said that his team of two dozen experts had already erected the first set of scaffolding on a small section of the World Heritage site and would start work in the next few days.

The work would continue until late March and resume in January next year for another three months, but the monument would remain open to the public throughout that time, he said.

The painstaking treatment would also be done in such small sections that it would not disturb tourists visiting the Taj — even those hoping to imitate the iconic Diana, Princess of Wales, photograph of 1992.

Ms Bruni, a former supermodel, is thought to be planning to visit the Taj Mahal alone this week while her partner, President Sarkozy of France, is in Delhi as part of an official visit to India.

Monument to love

- Mumtaz Mahal and Shah Jahan were inseparable – she even accompanied him when he went to war. She died giving birth to his fourteenth child

- Trees in the Taj garden are either cypresses (signifying death) or fruit-bearing types (signifying life)

- When Shah Jahan fell ill in 1657 one of his sons, Aurangzeb, took over the throne and imprisoned him. He died in 1666 and was entombed next to his beloved wife

Source: tajmahal.org.uk

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