Copper jumps to six-month high on supply worries, tight stocks

LONDON: Copper prices hit their highest in six months on Thursday as worries about tightening stocks outside the United States coincided with concerns about reduced supply of concentrates from the Democratic Republic of Congo.

Benchmark three-month copper on the London Metal Exchange was 1.2% higher at $14,275.50 a metric ton by 1005 GMT after hitting $14,369.5, the highest since the January 29 record of $14,527.5.

Congo banned exports of copper concentrate and cobalt concentrate as it tries to force domestic processing and retain more value from its mineral resources, according to a new government order reviewed by Reuters on Thursday.

The development inflated worries about supply and added to uncertainty over possible U.S. import tariffs, which kept COMEX copper above the LME benchmark and drew metal into U.S. warehouses.

COMEX copper futures hit a record high of $6.723 per lb on Thursday and traded at a premium against the LME contracts as the market continued to price in a potential U.S. import tariff decision.

The most active COMEX September contract was last up 1.3% at $6.817 per lb ($15,029 a ton).

The premium for LME cash copper over the three-month contract widened to $130 a ton, the most since October, signalling tightening conditions for near-term supply with total copper stocks in the LME-registered warehouses at 226,650 tons, the lowest since mid-February.

StoneX estimated at least 1.2 million tons of copper have entered the U.S. since February 2025, leaving about 64% of globally visible inventories in the country.

In other LME metals, nickel was down 2.2% at $16,735 a ton, having touched its lowest since July 13 at $16,565 after Chinese market information hub SMM reported that one of Indonesia’s nickel miners had received an additional quota for nickel ore production.

LME aluminium rose 0.4% to $3,253.50, zinc added 1.7% to $3,790, lead gained 0.5% to $1,894.50 and tin edged up 0.1% to $56,515.