A Chinese State-controlled mining company mothballed a cobalt processing plant in the Democratic Republic of Congo only 15 months after opening it due to a historic slump in the price of the battery metal.

MMG Lsaid it suspended operations at its new facility at the Kinsevere mine in December 2024 due to “unfavorable cobalt market conditions.” The government of Congo – which dominates production of the material used in electric vehicles – introduced a surprise four-month export ban last week to rein in oversupply and assert more control over the metal’s price.

The company – in which China Minmetals Corp owns a 67% stake – recently completed a project expected to cost as much as $600 million to increase copper output and start cobalt production at Kinsevere. The two metals are mined together in Congo, the world’s second-biggest source of copper.

While MMG started commissioning the cobalt plant in September 2023, the facility was placed in so-called care and maintenance at the end of last year, the company said when reporting annual results on Tuesday. The firm sold 1,600 tons of cobalt in 2024, according to the statement.

The firm has “implemented a flexible production strategy” in deciding when to resume cobalt operations that will be “based on prices,” a MMG spokesperson said in an email. Meanwhile, the company aims to increase copper production from Kinsevere by at least 40% this year.

Cobalt output in Congo – which accounts for about three-quarters of global production – has soared in recent years, as China’s CMOC Group ramped up output at two large mines in the Central African nation causing supply to outpace demand, sending prices tumbling.

On Feb. 24, the country imposed the shock ban on shipments while longer term policies to balance the market, including export quotas, remain under consideration.

Prices for cobalt hydroxide — the main product exported from Congo — have risen by a third following the ban, hitting $7.60 a pound on March 5., according to Fastmarkets. That’s the highest level since November 2023.

Hong Kong-listed MMG produced about 380,000 tons of copper last year from mines in Africa, Australia and South America. Las Bambas in Peru is by far the company’s largest asset.