Copper rallied to its highest level in more than three weeks early on Wednesday, as technical momentum gathered pace, and strong physical and Chinese buying and another hefty drawdown in inventories pointed to a tighter supply/demand balance.
Copper for September delivery on the COMEX metals division of the New York Mercantile Exchange surged 9.15 cents, or 3 percent, to settle at $3.0930 per lb, its loftiest level on a closing basis since June 25. Technicians said COMEX copper's ability to push through the top of a contracting triangle formation spurred additional technical momentum and short-covering.