<Tr> <Th> Material </Th> <Td> main structural system: reinforced concrete (lower part), steel / concrete composite construction, steel construction (upper part); cladding: glass, marble, natural stone, carbon - / glass - fibre - reinforced plastic </Td> </Tr> <Tr> <Th> Floor count </Th> <Td> 120 (Clock Tower) </Td> </Tr> <Tr> <Th> Floor area </Th> <Td> Tower: 310,638 m (3,343,680 sq ft) Development: 1,575,815 m (16,961,930 sq ft) </Td> </Tr> <Tr> <Th> Lifts / elevators </Th> <Td> 96 (Clock Tower) </Td> </Tr>

When was the clock tower in mecca built