mosque's grand chandelier with one made of bronze, which Terrasse described as "the largest and most beautiful chandelier in the Islamic world," and which hangs in the central nave of the mosque today. It was commissioned by Abu Muhammad 'Abd Allah ibn Musa, the khatib of the mosque during the years 1202 to 1219. The chandelier consists of a 12-sided copula on top of which is mounted a large cone crowned around its sides with nine levels of candlesticks. It could originally hold 520 oil candles; the cost of providing the oil was so significant that it was only lit on special occasions, such as on the nights of Ramadan. The Marinid sultan Abu Ya'qub Yusuf (ruled 1286–1307), upon seeing the cost, ordered that it only be lit for the last day of Ramadan. The visible surfaces of the chandelier are carved and pierced with intricate floral arabesque motifs as well as Kufic Arabic inscriptions. The chandelier is the oldest surviving chandelier in the western Islamic world, and it likely served as a model for the Marinid chandelier in the Great Mosque of Taza. Marinid period (13th–14th centuries) The Marinids, who were responsible for building many of the madrasas around Fez, made various contributions to the mosque. In 1286 they restored and protected the 10th-century minaret, which had been made from deteriorating poor-quality stone with whitewash. At its southern foot, they also built the Dar al-Muwaqqit, a chamber for the timekeeper (muwaqqit) of the mosque who was responsible for determining the precise times of prayer. The chamber was equipped with astrolabes and other scientific equipment of the era in order to aid in this task. Several water clocks were built for it in this period. The first two do not exist anymore, but are described by al-Jazna'i in the Zahrat al-As. The first was commissioned by Abu Yusuf Ya'qub in the 13th century and designed by Muhammad ibn al-Habbak, a faqih and muwaqqit. The second was built in 1317 or 1318 (717 AH), under the reign of Abu Sa'id, by a scholar named Abu Abdullah Muhammad al-Sanhaji. Its time divisions were engraved by Abu Abdullah Muhammad ibn al-Saddina al-Qarsatuni. The clock was neglected then restored between 1346 and 1349 (747–749 AH) by a new muwaqqit, Abu Abdullah Muhammad ibn al-'Arabi. A third and final water clock, built on the orders of Sultan Abu Salim Ali II (ruled 1359–1361), is still