Copper retreated from an earlier five-week high on Monday, snapping a four day rally as the struggling dollar strengthened and a strong aftershock in Japan unnerved some investors. Losses sped up later in the session after long-term commodity bull Goldman Sachs advised its clients in a note to close their long copper positions, which returned 23 percent since the investment bank's first recommendation to go long in October 2010.
COMEX May copper shed 4.15 cents to settle at $4.46 per lb, near the bottom of its $4.4555 to $4.5330 session range. Trading volumes remained brisk. More than 50,500 lots exchanged hands by 2:25 p.m. EDT (1825 GMT), in excess of 20 percent above the 30-day norm, according to Thomson Reuters preliminary data.