Exterior decoration of Taj Mahal

The exterior decorations of the Taj Mahal are among the finest to be found in Mughal architecture. As the surface area changes, a large pishtaq has more area than a smaller one, and the decorations are refined proportionally. The decorative elements were created by applying paint or stucco, or by stone inlays or carvings. In line with the Islamic prohibition against the use of anthropomorphic forms, the decorative elements can be grouped into either calligraphy, abstract forms or vegetative motifs.

The calligraphy found in Taj Mahal are of florid thuluth script, created by Persian calligrapher Amanat Khan, who signed several of the panels. The calligraphy is made by jasper inlaid in white marble panels, and the work found on the marble cenotaphs in the tomb is extremely detailed and delicate. Higher panels are written slightly larger to reduce the skewing effect when viewing from below. Throughout the complex, passages from the Qur'an are used as decorative elements. Recent scholarship suggests that Amanat Khan chose the passages as well.[3][4] The texts refer to themes of judgment and include:
Abstract forms are used especially in the plinth, minarets, gateway, mosque, jawab, and to a lesser extent, on the surfaces of the tomb. The domes and vaults of sandstone buildings are worked with tracery of incised painting to create elaborate geometric forms. On most joining areas, herringbone inlays define the space between adjoining elements. White inlays are used in sandstone buildings and dark or black inlays on the white marbles. Mortared areas of marble buildings have been stained or painted dark and thus creating a geometric patterns of considerable complexity. Floors and walkways use contrasting tiles or blocks in tessellation patterns.

Vegetative motifs are found at the lower walls of the tomb. They are white marble dados that have been sculpted with realistic bas relief depictions of flowers and vines. The marble has been polished to emphasise the exquisite detailing of these carvings. The dado frames and archway spandrels have been decorated with pietra dura inlays of highly stylised, almost geometric vines, flowers and fruits. The inlay stones are yellow marble, jasper and jade, leveled and polished to the surface of the walls.