Chile Copper Mine Faces 708-Worker Strike as Talks Fail

CHILE · MINING

Two unions at a major northern Chilean copper mine are ready to walk out over pay gaps.

A Chile copper mine strike could begin on Wednesday, 7 October, after mediation at Minera Centinela failed on Tuesday. Two unions with 708 members say they will walk out unless the company settles at the last minute.

The mine is controlled by Antofagasta Minerals, the Chilean arm of London-listed Antofagasta plc. Copper closed at US$6.58 a pound in London on Tuesday, according to Cochilco, Chile’s state copper commission.

What the Unions Want

The Minera Esperanza and Distrito Centinela unions have 708 members, the business daily Diario Financiero reported. In late September, 98.73% of their members voted to authorise a strike, with full turnout.

Their core demand is to end what they call discrimination in pay and benefits. They say their members earn less than workers in another union who do the same jobs.

The unions also want a mechanism that stops new gaps from opening during the next collective contract. They rejected the company’s final offer of Wednesday, 23 September, as not fixing existing gaps, the news site Emol reported.

“The assemblies have ratified the decision to strike if the company does not address a mechanism that prevents discrimination,” the unions said. On Tuesday they activated contingency plans for a walkout.

The final phase was mediation under Chile’s labour law, handled by the Labour Directorate, a labour ministry agency. That process closed on Tuesday without agreement, with the strike deadline set for midnight.

What the Company Says

Minera Centinela said it remains open to dialogue and wants to close the negotiation “in a responsible and constructive way”. It said it had made proposals throughout the talks.

“Minera Centinela does not discriminate against its workers for their union membership,” the company said. It argued that differences between contracts reflect earlier bargaining rounds and the specifics of each process.

Why Centinela Matters for Copper

Centinela produced 97,100 tonnes of copper in the first half of 2026, Antofagasta’s results show. That was 16% less than a year earlier but about a third of the group’s 285,000 tonnes.

The mine earned EBITDA, a measure of operating profit, of US$1,025.8 million in the first half. Antofagasta already cut its 2026 group target to 625,000 to 655,000 tonnes after a weather shutdown at another mine.

The company settled with Centinela’s supervisors’ union in the second quarter, signing a three-year deal. Its half-year report listed two more Centinela negotiations for the second half.

Cochilco data show London copper averaging about 40% more this year than in the same period of 2025. Diario Financiero noted that supply is already tight because of mine outages, natural events and lower ore grades.

Labour pressure is also building at Escondida, the BHP-run mine in the same region. Its supervisors’ union, with 1,009 members, voted 94.8% for a strike, and BHP requested mediation on Monday, 5 October, Reporte Minero reported.

What It Means for You

For US investors, Antofagasta plc trades in London, while BHP also has shares listed in New York. Copper futures in New York and US-listed producers such as Freeport-McMoRan tend to react to supply news from Chile.

For US industry, Chile is the largest foreign source of refined copper, according to the US Geological Survey. Copper goes into building wiring, power grids, data centres and electric cars, so tighter supply raises costs.

A single strike rarely moves prices for long on its own. The risk grows if several Chilean disputes, including Escondida’s, turn into stoppages at the same time.

What Is Not Known

It was not confirmed at publication whether the strike began on Wednesday or a late deal was reached. Neither side has said what share of Centinela’s workforce or output the 708 members represent.

The company has not disclosed its contingency plans. Neither side has published peso figures for the pay gap or for the final offer.

What Comes Next

Without a deal by midnight, the walkout starts with Wednesday’s shifts, and talks can continue during it. Chile’s 2016 labour reform bars employers from replacing striking workers.

A strike by two unions does not necessarily stop the whole mine. What it does mean is that a second bargaining front has opened in Chile’s copper heartland in the same week.

Frequently Asked Questions

What is Minera Centinela?

It is a copper and gold mining operation in Chile’s northern Antofagasta region. It is controlled by Antofagasta Minerals, part of London-listed Antofagasta plc.

Why are the workers ready to strike?

Two unions with 708 members say they are paid less than workers in another union for the same jobs. The company denies discriminating by union membership.

How much copper does Centinela produce?

Centinela produced 97,100 tonnes of copper in the first half of 2026. That was about a third of Antofagasta’s output in the period.

Can the company hire replacement workers?

No. Chile’s 2016 labour reform bars employers from replacing striking workers.

Will the strike raise copper prices in the US?

Not on its own unless it lasts. A long stoppage, especially alongside other Chilean disputes, would add to supply worries that already keep prices high.

Sources: Antofagasta plc, 2026 half-year results; Antofagasta plc, Q2 2026 production report; Cochilco, daily copper report, 6 October 2026; Diario Financiero (6 October); Diario Financiero (28 September); Emol; Reporte Minero (all accessed 7 October 2026).