Copper prices were on track for a weekly gain of 2.0% on Friday, supported by concerns over mine supply disruptions, signs of active demand in top consumer China and tight visible inventories outside the US.
Benchmark three-month copper on the London Metal Exchange was up 1.8% at $14,565 a metric ton in official open-outcry trading.
The Yangshan copper premium - a gauge of China's appetite for imported copper - ended this week at $135 a ton, its four-year high, as the country returned from a week-long holiday.
Copper inventories in warehouses monitored by the Shanghai Futures Exchange stood at 58,744 tons at the end of the week, up 20,000 tons from end-September, when stocks had fallen to their lowest level since January 2024.
Meanwhile, copper stocks in the LME-registered warehouses dropped to a six-week low of 233,025 tons after daily outflows of 4,700 tons, mainly from warehouses in Taiwan and Hong Kong, exchange data showed.
Copper prices have been supported since 2025, particularly over the past six months, by persistent transfers of metal into Comex warehouses amid uncertainty over potential US import tariffs on refined copper. Comex inventories currently stand at a record 711,609 tons.
Tightness in nearby supply on the LME remained evident, with the cash copper contract ending Thursday at a premium of $97 a ton to the three-month contract.
"Any slowdown in US stockpiling could make the market feel looser, but China's demand has been resilient and supply is facing significant disruptions," Morgan Stanley said in a note.
A union at Antofagasta's Centinela copper mine in Chile said the ongoing strike would begin to weigh on output in November. Antofagasta earlier downplayed the impact of the strike, but the situation added to the risk of disruptions at other mines.
Among other LME metals, aluminium rose 0.6% to $3,069 a ton in official activity, zinc gained 1.7% to $3,781, lead added 1.2% to $1,883, tin climbed 3.0% to $53,000 and nickel was up 1.0% at $15,710.
