empires, was the colorful tiles, with which they covered the exterior of their domes, as they would on the interior. These domes soon numbered dozens in Isfahan, and the distinct, blue-colored shape would dominate the skyline of the city. Reflecting the light of the sun, these domes appeared like glittering turquoise gem and could be seen from miles away by travelers following the Silk road through Persia. Reaching 53 meters in height, the dome of the Masjed-e Shah would become the tallest in the city when it was finished in 1629. It was built as a double-shelled dome, with 14 meters spanning between the two layers, and resting on an octagonal dome chamber. Art The Masjed-e Shah was a huge structure, said to contain 18 million bricks and 475,000 tiles, having cost the Shah 60,000 tomans to build. It employed the new haft rangi (seven-colour) style of tile mosaic. In earlier Iranian mosques the tiles had been made of faience mosaic, a slow and expensive process where tiny pieces are cut from monochrome tiles and assembled to create intricate designs. In the haft rangi method, artisans put on all the colors at once, then fired the tile. Cheaper and quicker, the new procedure allowed a wider range of colors to be used, creating richer patterns, sweeter to the eye. According to Jean Chardin, it was the low humidity in the air in Persia that made the colors so much more vivid and the contrasts between the different patterns so much stronger than what could be achieved in Europe, where the colors of tiles turned dull and lost its appearance. Still, most contemporary and modern writers regard the tile work of the Masjed-e Shah as inferior in both quality and beauty compared to those covering the Lotfallah Mosque, the latter often referred to by contemporary Persian historians, such as Iskandar Munshi, as the mosque of great purity and beauty. The architects also employed a great deal of marble, which they gathered from a marble quarry in nearby Ardestan. Throughout the building, from the entrance portal and to the main building, the lower two meters of the walls are covered with beige marble, with beautifully carved poles at each side of every doorway and carved inscriptions throughout. Above this level begins the mosaic tiles that cover the rest of the building. The entrance portal of the mosque displays the finest tile decoration