Base metals closed the day mostly lower on the London Metal Exchange Tuesday amid relatively subdued trade as market players continued to eye macro headlines.

At the PM kerb close, flagship three-month copper was down 2.7% at $6,800 a metric ton. Tin stood alone in positive territory, up 2.4% on the day at $20,990/ton.

Base metal markets were quieter than usual Tuesday, as many market players were away from their desks during the LME's annual industry week. This added to a sense of directionless, with remaining market participants reacting to macroeconomic news, industry players said.

U.S. Federal Reserve Chairman Ben Bernanke's prepared remarks to a bipartisan Congressional panel gave equity markets a slight lift Tuesday, after he initially appeared to suggest that a third round of quantitative easing might not be far away. Base metals followed equities higher in the wake of the comments, although gains were later pared somewhat.

Meanwhile, fresh newsflow on the euro-zone debt crisis was relatively thin Tuesday, after euro-zone finance ministers said Monday they would delay a decision on whether and when to provide another round of financial support for debt-laden Greece.

"With markets waiting for macro economic data later this week (U.S. non-farm payrolls) and the ECB rate decision, combined with LME week, we expect quiet conditions in the base metals markets today and tomorrow," said Standard Bank analyst Leon Westgate in a note.

Tuesday saw several banks and industry watchers downgrade their base metal forecasts. Goldman Sachs cut its average 2012 copper price by 14.7% to $9,200/ton after lowering its global economic growth expectation. The bank also reduced its outlook for oil.

Among other entities to downgrade their outlook on base metals were Standard Bank, Credit Suisse and aluminum analysis firm Harbor Intelligence, which cut its forecasts for aluminum in 2011 and 2012.

 
   Prices in dollar a metric ton. 
3 Months Metal             Bid-Ask        Change from 
                                          Monday PM kerb 
Copper                  6800.0-6801.0     Dn 190 
Lead                    1886.0-1887.0     Dn 75 
Zinc                    1860.0-1861.0     Dn 33 
Aluminum                2173.0-2174.0     Dn 30 
Nickel                18700.0-18800.0     Dn 320 
Tin                   20990.0-20995.0     Up 490 
Aluminum Alloy          2145.0-2150.0     Dn 25 
Aluminum Alloy-NASAAC   2255.0-2260.0     Dn 30

-By Francesca Freeman, Dow Jones Newswires; +44 (0)20 7842 9412; francesca.freeman@dowjones.com