Origins and architecture of the Taj Mahal leading classes of Indian social structure and thus defined themselves as rulers in Indian terms. Red sandstone also had significance in the Persian origins of the Mughal empire where red was the exclusive colour of imperial tents. In the Taj Mahal the relative importance of each building in the complex is denoted by the amount of white marble (or sometimes white polished plaster) that is used. The use of naturalist ornament demonstrates a similar hierarchy. Wholly absent from the more lowly jilaukhana and caravanserai areas, it can be found with increasing frequency as the processional route approaches the climactic Mausoleum.
Taj Mahal the government erected scaffolding to disguise the building in anticipation of air attacks by the Japanese Air Force. During the India-Pakistan wars of 1965 and 1971, scaffolding was again erected to mislead bomber pilots. More recent threats have come from environmental pollution on the banks of the Yamuna River including acid rain due to the Mathura Oil Refinery, which was opposed by Supreme Court of India directives. The pollution has been turning the Taj Mahal yellow. To help control the pollution, the Indian government has set up the Taj Trapezium Zone (TTZ), a area around the monument where strict emissions