By David Hodari and Amrith Ramkumar

Copper prices swung between small gains and losses before closing slightly lower on Tuesday, with traders looking ahead to the next trade updates from the U.S. and China.

Front-month copper for September delivery closed down 0.4% at $2.8035 a pound on the Comex division of the New York Mercantile Exchange. Prices have rebounded lately after entering bear-market territory this summer, though they are still well below their June four-year highs amid worries that a tariff fight between the U.S. and China will weaken the global economy and limit consumption.

China is the world's largest consumer of industrial metals broadly, accounting for about half of global copper demand.

Although the U.S. and China have laid out plans to end their tariff fight ahead of planned November meetings between leaders from both countries, the latest duties from both sides took effect on Monday.

China also canceled trade talks that were planned for this week.

Analysts are also keeping an eye on the dollar, which has fallen lately after hitting a 15-month high last month. A weaker dollar makes commodities cheaper for overseas buyers and has helped materials stabilize following punishing drops in the summer. The WSJ Dollar Index, which tracks the dollar against a basket of 16 other currencies, was down less than 0.1% Tuesday.

Among precious metals, front-month gold for September delivery added less than 0.1% to $1,200 a troy ounce. Prices have fallen about 8.1% this year, hurt by the dollar's stability and higher short-term Treasury yields that have made gold less attractive to some investors. Traders were looking ahead to Wednesday's statement from the Federal Reserve for the latest reading on the central bank's plan for interest-rate increases.

Elsewhere in precious metals, most-actively traded silver futures rose 1.1% to $14.493 a troy ounce. Platinum was down 0.8% at $822.90, while palladium climbed 0.2% to $1,053.80 in a 10th straight session of gains.

On the London Metal Exchange, aluminum for delivery in three months inched up 0.4% to $2,067.50 a metric ton. Zinc dropped 1.9% to $2,515, tin was down 0.1% at $18,900 and nickel edged down less than 0.1% to $12,950. Lead fell 1.6% to $2,009.50.

Write to David Hodari at David.Hodari@dowjones.com and Amrith Ramkumar at amrith.ramkumar@wsj.com

(END) Dow Jones Newswires

September 25, 2018 15:05 ET (19:05 GMT)

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