Origins and architecture of the Taj Mahal AD (1053 AH) the official sources documenting the twelfth Urs give a detailed description of a substantially completed complex. Decorative work apparently continued until 1648 AD (1058 AH) when Amanat Khan dated the north arch of the great gate with the inscription "Finished with His help, the Most High". The Taj Mahal was constructed using materials from all over India and Asia. The buildings are constructed with walls of brick and rubble inner cores faced with either marble or sandstone locked together with iron dowels and clamps. Some of the walls of the mausoleum are several metres thick. Over 1,000
Taj Mahal mausoleum was essentially completed in 1643 but work continued on other phases of the project for another 10 years. The Taj Mahal complex is believed to have been completed in its entirety in 1653 at a cost estimated at the time to be around 32 million rupees, which in 2015 would be approximately 52.8 billion rupees (U.S. $827 million). The construction project employed some 20,000 artisans under the guidance of a board of architects led by the court architect to the emperor, Ustad Ahmad Lahauri. The Taj Mahal was designated as a UNESCO World Heritage Site in 1983 for being