Copper Holds Weekly Gain on Chilean Strike Risk as LME Stocks Drop to Six-Week Low

Copper booked a weekly gain on October 9 as mine supply risk and firmer Chinese demand signals offset a stronger dollar earlier in the week, with stocks in LME-registered warehouses dropping to a six-week low. Three-month copper on the London Metal Exchange settled at $14,550.00 a tonne, up $255.50 or 1.79% on the session, according to Xinhua Finance's daily LME close. The rest of the complex followed: zinc rose 2.47% to $3,801.50 a tonne to lead the complex, tin gained 2.92% to $53,000, lead added 1.18% to $1,885.50, nickel rose 0.96% to $15,700 and aluminium was the laggard, up 0.49% at $3,057.00.

The supply side is doing most of the work. Unions at Antofagasta escalated their stoppage with a hunger protest and projected that copper output could fall by about 50% in November if the strike is not resolved. Separately, the Centinela copper mine and two unions agreed to resume negotiations on a Tuesday under a voluntary mediation process after a strike that began on October 7, with the union warning that production could start to fall within roughly two weeks. Chilean outage risk is being layered onto an already tight concentrate market, with treatment charges depressed and smelters competing for feed.

Refined balances remain finely poised even so. Global refined copper is marginally oversupplied, but the surplus is concentrated in Comex warehouses where inventories keep building, while supply outside the United States is tightening at the margin. In China, September refined copper output from smelters surveyed by SMM came to 1.1206 million tonnes, down 2.3% month on month, as concentrated maintenance met tight scrap supply. That combination of non-US tightness and mine-side disruptions is what has put a floor under prices rather than any broad demand surge.

Tin and zinc have their own micro stories feeding the same direction. LME tin stocks fell 225 tonnes to 4,265 tonnes and cancelled warrants dropped 367 tonnes to 3,994 tonnes, lifting the spot-to-three-month spread, even as China's August tin ore imports hit a two-and-a-half year high of 19,332 tonnes with Myanmar contributing 7,395 tonnes as Wa State shipments resumed after the rainy season. Zinc drew support from thin offshore inventories. On the macro side, the dollar index gave back gains after four straight weekly advances, which lowered the holding cost of dollar-priced metal and gave the whole complex a valuation window.