A definitive number of jobs to go was not released and the company said redundancies were the last resort. However, about 1200 people were employed in the mines and the copper concentrator.

It said this morning that it had notified its workers that after 60 years of copper mining, the Mount Isa Mines underground copper operations (Enterprise, X41 and Black Rock) and copper concentrator will close in the second half of 2025.

Glencore’s copper smelter and refinery have been given a life only until 2030, subject to approval of additional capital investment.

The mine closure was likely to have a devastating impact on the town of 18,000 where they have been the economic lifeblood, but the ore reserves were limited and were extended by a massive capital investment.

The George Fisher Mine, zinc-lead concentrator, and lead smelter in Mount Isa, as well as the copper refinery in Townsville, will all continue operating and were described as “long life”.

The implications from the closure could be significant with job losses likely to have a flow-on effect on the town which is the heart of the Katter political dynasty.

The State Government has already announced a $50 million support package. About $30 million of the funds would go to speeding up the development of other mining projects in the area and $20 million would be in the form of an economic structural adjustment package for the town.

Premier Annastacia Palaszczuk said for 100 years, Mt Isa had been part of Queensland’s mining heritage.

“We’re determined Mt Isa and north west Queensland will be at the heart of our state’s mining future as well,” she said.

“Our number one priority is to protect jobs and retain skilled workers in this important region. ”

Treasurer Cameron Dick promised the Government would back the city and the region “all the way”.

Glencore zinc assets chief operating officer in Australia Sam Strohmayr said the Mt Isa copper operations “had come to the end”.

“That’s been a difficult decision which we have not made lightly,” he said.

“The last six years of mining have been very challenging. We have seen falling production, declining ore grades and we are at a point where every tonne of ore barely contains enough copper to pay for its extraction.”

There are mineral reserves left, but were considered too deep and difficult.

The job losses were going to be structured and “gradual”, but with a time limit put on both the mines and the smelter, Glencore’s next problem may be keeping workers.

In a statement, Glencore said it had conducted a range of studies and reviews seeking to further extend the life of the underground copper mines, but unfortunately it has not been possible, and they have reached the end of mine life.

“The studies revealed that the remaining mineral resources are not economically viable due to low ore grades and areas where, due to geological conditions, safe extraction can’t be achieved using current technology, this all coupled with ageing infrastructure.”

The company said its Lady Loretta zinc mine, located 140 kilometres north-west of Mount Isa, which was a finite orebody with a seven-year mine life would also close in 2025.

Glencore zinc assets chief operating officer in Australia Sam Strohmayr said the company was aware of the impact of the decision.

“We know this decision will be disappointing for our people, our suppliers, and the Mount Isa community. The reality of mining is that mines have a beginning, middle and end. And unfortunately, after 60 years of operation, Mount Isa’s underground copper operations have now reached that end,” he said.

“We want to give our people as much time as possible to consider the best options for them and their families, which is why we are notifying our workers and the community almost two years before these mines close.

“Our focus over the coming months will be to work closely with our people and contractors, our suppliers, and the Mount Isa community to provide support as we move towards closure of these assets.

“Our Mount Isa underground copper mines, copper concentrator and supporting services currently employ around 1200 people.

“It’s too early to put a figure on how many people may receive redundancies until we work through a process of speaking to each worker and discuss options around retention, redeployment, and retraining. Redundancies are the last resort and will be offered only when other options have been exhausted.”

“Glencore will continue to invest in the long-term future of Mount Isa Mines, including the George Fisher Mine with a current life of mine to 2036, and our zinc-lead concentrator and lead smelter.

“We also expect the copper smelter and refinery to continue operating to 2030, subject to approval of additional capital investment.

“These are important strategic assets, not just for Glencore but for the North West Minerals Province and the future of Queensland’s critical minerals industry.”

Treasurer Cameron Dick was in Mt Isa to talk with local workers and unions.

Mt Isa is also at the heart of the north west minerals province, which both the industry and the State Government had been promoting as a massive undiscovered mineral resource.