Japan’s Mitsui to sell stake in Caserones copper mine in Chile

Mitsui is to sell all of its 22.63% stake in Chile's Caserones copper mine, after posting a capital loss of more than ¥7 billion ($67.5 million), the Japanese company said on Monday November 9.

Mitsui has already informed the majority owner of Caserones, JXTG, which also controls Japan’s biggest copper smelter, Pan Pacific Copper.

The sale of the loss-making copper mine is being “executed as a part of [Mitsui’s] reorganization and reconstructing of [its] asset portfolio,” the Japanese company said. 

Mitsui acquired the stake in Caserones in 2010. At the time, had a planned annual capacity of 150,000 tonnes of copper concentrate and 30,000 tonnes of copper cathodes.

Located at the head of a valley in the Atacama region of Chile, Caserones is a low-grade copper deposit exposed to extreme weather in an area with water shortages – making it prone to low-level operations and resulting in high ramp-up costs. 

In 2018, JXTG posted an impairment loss of ¥65 billion ($606.8 million) following a review of its long-term mining plan after a fault in an ore pit. 

Last month, Japanese conglomerate Sumitomo also put its 45% stake in the Sierra Gorda copper-molybdenum mine in northern Chile up for sale. 

Mitsui’s  offloading announcement comes despite the red metal price rebounding strongly in recent months. The three-month copper price on the London Metal Exchange was $6,968 per tonne on the morning of November 9, up 31% from six months ago.

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