Copper declined to its weakest level since August 2012 after a report showed that manufacturing in the U.S. and China, the largest consumers, advance at the slower pace than expected, while aluminium fell to its lowest level since October. Copper for July delivery slid 1.3% to $7,440 a metric ton in London and it was traded at $7,493 in Tokyo, whereas aluminium dropped 0.6% to $1,893 a ton.