Short answers, pulled from the story.
Shah Jahan commissioned the Taj Mahal in 1632 after the death of his wife Mumtaz Mahal on the 17th of June 1631. Construction of the mausoleum began in 1632 and utilized a workforce of more than 20,000 artisans, laborers, and craftsmen from across the globe.
The Taj Mahal was designed by the emperor's court architect Ustad Ahmad Lahori using white marble inlaid with 28 types of precious and semi-precious stones. Materials included jade and crystal from China, turquoise from Tibet, lapis lazuli from Afghanistan, sapphire from Sri Lanka, and carnelian from Arabia.
The Taj Mahal is located on the southern bank of the Yamuna River in Agra, India, within a vast charbagh garden divided into four quadrants. The main tomb is positioned at the end of the garden rather than in the center, featuring a raised marble water tank known as al Hawd al-Kawthar that mirrors the image of the mausoleum.
No, the idea of a Black Taj Mahal is a persistent myth originating from the writings of Jean-Baptiste Tavernier in 1665. Excavations in the 1990s proved that ruins of blackened marble in the Mehtab Bagh were actually discolored white stones, and a more credible theory suggests the dark reflection was intended for visual symmetry.
Shah Jahan was deposed by his son Aurangzeb in 1658 and imprisoned in the nearby Agra Fort until his death in 1666. Aurangzeb buried him in the mausoleum next to his wife, creating an asymmetrical arrangement in the lower tomb chamber.
The Taj Mahal was designated a UNESCO World Heritage Site in 1983 and declared a winner of the New 7 Wonders of the World initiative in 2007. Modern challenges include environmental pollution from the nearby Mathura Oil Refinery which has turned the white marble yellow-brown, leading to the establishment of the Taj Trapezium Zone in 1997.