<P> The minarets, which are each more than 40 metres (130 ft) tall, display the designer's penchant for symmetry . They were designed as working minarets--a traditional element of mosques, used by the muezzin to call the Islamic faithful to prayer . Each minaret is effectively divided into three equal parts by two working balconies that ring the tower . At the top of the tower is a final balcony surmounted by a chattri that mirrors the design of those on the tomb . The chattris all share the same decorative elements of a lotus design topped by a gilded finial . The minarets were constructed slightly outside of the plinth so that in the event of collapse, a typical occurrence with many tall constructions of the period, the material from the towers would tend to fall away from the tomb . </P> <P> The exterior decorations of the Taj Mahal are among the finest in Mughal architecture . As the surface area changes, the decorations are refined proportionally . The decorative elements were created by applying paint, stucco, 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 . Throughout the complex are passages from the Qur'an that comprise some of the decorative elements . Recent scholarship suggests that the passages were chosen by Amanat Khan . </P> <P> The calligraphy on the Great Gate reads "O Soul, thou art at rest . Return to the Lord at peace with Him, and He at peace with you ." The calligraphy was created in 1609 by a calligrapher named Abdul Haq . Shah Jahan conferred the title of "Amanat Khan" upon him as a reward for his "dazzling virtuosity". Near the lines from the Qur'an at the base of the interior dome is the inscription, "Written by the insignificant being, Amanat Khan Shirazi ." Much of the calligraphy is composed of florid thuluth script made of jasper or black marble inlaid in white marble panels . Higher panels are written in slightly larger script to reduce the skewing effect when viewed from below . The calligraphy found on the marble cenotaphs in the tomb is particularly detailed and delicate . </P> <P> Abstract forms are used throughout, especially in the plinth, minarets, gateway, mosque, jawab and, to a lesser extent, on the surfaces of the tomb . The domes and vaults of the sandstone buildings are worked with tracery of incised painting to create elaborate geometric forms . Herringbone inlays define the space between many of the adjoining elements . White inlays are used in sandstone buildings, and dark or black inlays on the white marbles . Mortared areas of the marble buildings have been stained or painted in a contrasting colour which creates a complex array of geometric patterns . Floors and walkways use contrasting tiles or blocks in tessellation patterns . </P>

The inscriptions on the exterior of the taj mahal were designed by