By Christopher Alessi and Amrith Ramkumar

Copper prices fell for the fourth consecutive session Tuesday as fresh worries about the global economy hit commodities across the board.

Copper for March delivery slumped 1.8% to $2.7050 a pound on the Comex division of the New York Mercantile Exchange.

Prices are down about 18% from their June four-year highs and on track for a fourth consecutive quarterly decline, dragged down by fears that a global economic slowdown will lower demand for materials used heavily in manufacturing and construction.

Weak economic figures from China, in particular, have hurt industrial metals such as copper lately, as the country is the world's largest commodity consumer and accounts for about half of global copper demand. The continuing U.S.-China trade fight has also stoked demand worries, analysts say.

Stocks around the world and other commodities including oil have slid lately, a sign to some investors that concerns about the global economy are growing more pronounced late in the year.

Analysts were looking ahead to the Federal Reserve's latest interest-rate decision, expected Wednesday afternoon following the central bank's two-day meeting, for the next event that could impact sentiment about economic growth.

Elsewhere in base metals, aluminum for delivery in three months fell 0.2% to $1,938.50 a metric ton on the London Metal Exchange. Zinc dropped 0.6% to $2,524, tin slipped 0.8% to $19,190, nickel was down 0.2% at $10,965 and lead rose 0.7% to $1,944.50.

Among precious metals, Comex gold for February inched up less than 0.1% to $1,252 a troy ounce, around its highest level since July thanks to a weaker dollar that makes the metal cheaper for overseas buyers. Most-active silver futures fell 0.4% to $14.70 a troy ounce, platinum was down 0.6% at $791 and palladium inched up 0.4% to $1,186.40.

Write to Christopher Alessi at christopher.alessi@wsj.com and Amrith Ramkumar at amrith.ramkumar@wsj.com

(END) Dow Jones Newswires

December 18, 2018 09:44 ET (14:44 GMT)

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