faience, show up in Timur's earliest buildings, such as the Aq Saray palace in Shahrisabz, in Uzbekistan, which was begun in 1379 but was still unfinished in 1404. Tekesh Mausoleum This structure is the presumed Tomb of Sultan Ala al-Din Tekish, the founder of the Khwarazmian Empire and its ruler between 1172-1200. It has been identified as a mausoleum due to the tradition that each ancient Central Asian building is dedicated to a historical or mythical personage. The building is made of bricks and consists of a square hall with walls which are 11,45 meters high, a massive round drum and a conical roof with an inner dome hidden under it. The dome is connected to the square walls it rests upon by an octagonal belt. The structure between the dome and the octagon is decorated with 16 shallow niches. Their form is not lancet-like as those commonly found in the Islamic architecture of Central Asia, but rather semicircular. This is a motif that can be found in the marble 8th-century mihrab at the Baghdad Museum, and has seldom been used in Central Asia: another comparable case that can be found in Turkmenistan is that of the mihrab of Muhammad Ibn Zayd's 11th-century mosque, from Merv. However, the two are located too far away to be considered prototypes. The external conical roof is built of horizontal layers using the technique of a false vault. From the inside, it is strengthened with 12 buttresses standing upon the internal dome. Although this might seem like a risky construction technique, the roof is not in bad condition: only the top is destroyed, and the blue majolica decoration slightly damaged. One of the special features of the building's architecture is its façade. It presents a high portal niche with the main archway, which has now lost its original form. The lancet arch of the portal is filled by a complicated system of stalactite -like forms, which is a decorative motif made of terracotta and fixed on wooden sticks within the brickwork. Research concerning this structure has given rise to speculations that the Mausoleum of Tekesh might have stood at the centre of some large construction that consisted of a multitude of buildings. Thus, certain scholars would argue that the building served a different purpose from that of a mausoleum, such as, for example, a House of Government or a Palace of the Great Khwarzm-shahs.