It was a summer shoot-out between two of the biggest copper traders in the business — investment bank Barclays Capital betting prices would rise and London hedge fund Red Kite expecting them to fall. Red Kite won, hands down. The head of metals trade at Barclays Capital and a colleague were leaving the company on Thursday after losing tens of millions of dollars on London Metal Exchange (LME) copper, compounded by losses on aluminium futures, trading sources said. They were named by dealers as Iain Macrae, head of the metals desk at Barclays, and Christian Saunders. Barclays would not confirm the identity of those departing. Neither could be reached for comment. Barclays would not specify the scale of the losses but said they were not \"big\" and that there was no \"abnormal\" trade, a reference to rogue trading. Traders said Macrae, said to be responsible for the biggest book on the LME, went long in copper in the summer betting that warehouse stocks would fall. He ordered long positions on outright copper prices, spreads and options. Barclays in August had bought a stake in Erus Metals, a small metals warehouse in Europe, to help manage its trading position and to secure a foothold in the profitable storage business. One large bet was on a widening spread of Dec-ember 2012 copper over December 2013. Macrae was up against the most renowned trading team in metals, Red Kite\'s Michael Farmer and David Lilley. \"Barcap got stung by Red Kite,\" a veteran LME trader said. Known for its connections in China, Red Kite decided demand from the world\'s biggest copper consumer was suffering from a spike to $10,000 a tonne in copper earlier in the year. It shorted the market. Farmer and Lilley also ensured they had the metal to deliver against their short position in case they needed it. \"Farmer was a big short and made sure he had the copper to deliver in case he got squeezed. That\'s what eased the spread,\" said the trade