Editor’s note: Albert Yuma Mulimbi, chairman of Congo’s state-owned mining company, was dismissed from his position on Saturday.

KASULO, Congo — A man in a pinstripe suit with a red pocket square walked around the edge of a giant pit one April afternoon where hundreds of workers often toil in flip-flops, burrowing deep into the ground with shovels and pickaxes.

His polished leather shoes crunched on dust the miners had spilled from nylon bags stuffed with cobalt-laden rocks.

The man, Albert Yuma Mulimbi, is a longtime power broker in Congo and chair of a government agency that works with international mining companies to tap the nation’s copper and cobalt reserves, used in the fight against global warming.

Yuma’s professed goal is to turn Congo into a reliable supplier of cobalt, a critical metal in electric vehicles, and shed its anything-goes reputation for tolerating an underworld where children are put to work and unskilled and ill-equipped diggers of all ages get injured or killed.

“We have to reorganize the country and take control of the mining sector,” said Yuma, who had pulled up to the Kasulo site in a fleet of SUVs carrying a high-level delegation to observe the challenges there.

But to many in Congo and the United States, Yuma himself is a problem. As chair of Gécamines, Congo’s state-owned mining enterprise, he has been accused of helping to divert billions of dollars in revenues, according to confidential State Department legal filings reviewed by The New York Times and interviews with a dozen current and former officials in both countries.

Top State Department officials have tried to force him out of the mining agency and pushed for him to be put on a sanctions list, arguing he has for years abused his position to enrich friends, family members and political allies.

Yuma denies any wrongdoing and is waging an elaborate lobbying and legal campaign to clear his name in Washington and Congo’s capital of Kinshasa, all while pushing ahead with his plans to overhaul cobalt mining.

Effectively operating his own foreign policy apparatus, Yuma has hired a roster of well-connected lobbyists, wired an undisclosed $1.5 million to a former White House official, offered the United States purported intelligence about Russia and critical minerals and made a visit to Trump Tower in New York, according to interviews and confidential documents.

Yuma met with Donald Trump Jr. there in 2018, a session the mining executive described as a quick meet-and-greet. Despite such high-level access during the Trump administration, he was barred just two months later from entering the United States.

His grip on the mining industry has complicated Congo’s effort to attract new Western investors and secure its place in the clean energy revolution, which it is already helping to fuel with its vast wealth of minerals and metals like cobalt.

Batteries containing cobalt reduce overheating in electric cars and extend their range, but the metal has become known as “the blood diamond of batteries” because of its high price and the perilous conditions in Congo, the largest producer of cobalt in the world. As a result, carmakers concerned about consumer blowback are rapidly moving to find alternatives to the element in electric vehicles, and they are increasingly looking to other nations with smaller reserves as possible suppliers.

There is a chance that Congo’s role in the emerging economy could be diminished if it fails to confront human-rights issues in its mines. And even if Yuma works to resolve those problems, as he has pledged to do, it still may not be enough for new American investors who want to be assured the country has taken steps to curb a history of mining-industry corruption.

Congo’s president, Felix Tshisekedi, has tried to sideline Yuma by stacking Gécamines with his own appointees, but he has been unwilling to cross him further. During an interview at his hillside palace in Kinshasa, Tshisekedi said he had his own strategy for fixing the country’s dangerous mining conditions.

“It is not going to be up to Mr. Yuma,” he said. “It will be the government that will decide.”

The standoff between Yuma and the president echoes power struggles that have torn apart African countries rich with natural resources in the past. How this one plays out has implications that reach far beyond the continent, as the global battle against climate change calls for a stepped-up transition from gasoline-burning vehicles to battery-powered ones.

For Congo, the question boils down to this: Will Yuma help the country ride the global green wave into an era of new prosperity, or will he help condemn it to more strife and turmoil?

Statues greet motorists at the main roundabout in a mining hub in Congo’s Copperbelt. One depicts an industrial miner in hard hat, headlamp and boots; another a shoeless, shirtless man in ragged shorts holding a pickax. They tell the story of the country’s dual mining economies: industrial and artisanal.

High-tech, industrial mines run by global corporations like China Molybdenum employ thousands of people in Congo’s cobalt sector, and while they have their own problems, they are largely not responsible for the country’s tarnished reputation abroad.

It’s a different story for the artisanal sector, where Yuma plans to focus the bulk of his stated reforms. Consisting of ordinary adults with no formal training, and sometimes even children, artisanal mining is mostly unregulated and often involves trespassers scavenging on land owned by the industrial mines. Along the main highway bisecting many of the mines, steady streams of diggers on motorbikes loaded down with bags of looted cobalt — each worth about $175 — dodge checkpoints by popping out of sunflower thickets.

Unable to find other jobs, thousands of parents send their children in search of cobalt. On a recent morning, a group of young boys were hunched over a road running through two industrial mines, collecting rocks that had dropped off large trucks.

The work for other children is more dangerous — in makeshift mines where some have died after climbing dozens of feet into the earth through narrow tunnels that are prone to collapse.

Kasulo, where Yuma is showcasing his plans, illustrates the gold-rush-like fervor that can trigger the dangerous mining practices. The mine, authorized by Gécamines, is nothing more than a series of crude gashes the size of city blocks that have been carved into the earth.

Georges Punga is a regular at the mine. Now 41, Punga said he started working in diamond mines when he was 11. Ever since, he has traveled the country searching Congo’s unrivaled storehouse for treasures underfoot: first gold, then copper, and, for the past three years, cobalt.

Punga earns less than $10 a day — just enough, he said, to support his family and keep his children in school instead of sending them to the mines.

“If I could find another job, I’d do it,” he said. “I’m tired of digging.”

Officials in Congo have begun taking corrective steps, including creating a subsidiary of Gécamines to try to curtail the haphazard methods used by the miners, improve safety and stop child labor, which is already illegal.

As chair of the board of directors, Yuma is at the center of these reforms. That leaves Western investors and mining companies that are already in Congo little choice but to work with him as the growing demand for cobalt makes the small-scale mines — which account for as much as 30% of the country’s output — all the more essential.

Once the cobalt is mined, a new agency will buy it from the miners and standardize pricing for diggers, ensuring the government can tax the sales. Yuma envisions a new fund to offer workers financial help if cobalt prices decline.

Right now, diggers often sell the cobalt at a mile-long stretch of tin shacks where the sound of sledgehammers smashing rocks drowns out all other noise.

Seeking solutions for the artisanal mining problem is a better approach than simply turning away from Congo, argues the International Energy Agency, because that would create even more hardships for impoverished miners and their families.

But activists point out that Yuma’s plans, beyond spending money on new buildings, have yet to really get underway, or to substantially improve conditions for miners.

Yuma is one of Congo’s richest businessmen. He secured a prime swath of riverside real estate in Kinshasa where his family set up a textile business that holds a contract to make the nation’s military uniforms. A perpetual flashy presence, he is known for his extravagance. People still talk about his daughter’s 2019 wedding, which had the aura of a Las Vegas show, with dancers wearing light-up costumes and large white giraffe statues as table centerpieces.

He has served on the board of Congo’s central bank and was reelected this year as president of the country’s powerful trade association, the equivalent of the U.S. Chamber of Commerce.

The huge mining agency where he is chair was nationalized and renamed under President Mobutu Sese Seko after Congo gained independence from Belgium in 1960. Gécamines once had a monopoly on copper and cobalt mining and, by the 1980s, was among the top copper producers in the world. Jobs there offered a good salary, health care and schooling for employees’ families.

But Mobutu, who ruled for 32 years, raided its funds to support himself and his cronies, a pattern followed by his successors, according to anti-corruption groups. By the 1990s, production from Gécamines had declined dramatically. Money wasn’t reinvested into operations, and the agency amassed debt of more than $1 billion. Eventually, half of its workforce was laid off.

To survive, Gécamines was restructured, turning to joint ventures with private, mostly foreign, investors in which the agency had a minority stake.

Yuma took over in 2010, promising to return Gécamines to its former glory. But instead, according to anti-corruption groups, mining revenues soon disappeared. The Carter Center, a nonprofit, estimated that between 2011 and 2014 alone some $750 million vanished from Gécamines’ coffers, placing the blame in part on Yuma.

Tshisekedi and Yuma walked near a large terraced canyon at one of Glencore’s cobalt mines in the Copperbelt, a region so defined by mining that roadside markets sell steel-toed boots and hard hats alongside fresh eggs and spears of okra.

The outing in May was awkward for these two political rivals.

Tshisekedi, a longtime opposition member who took office in early 2019 in a disputed election, has been fully embraced by the Biden administration, which sees him as an ally in battling global warming. He is chair of the African Union and has repeatedly appeared with President Joe Biden at international events, including a meeting in Rome last month and then again a few days later in Glasgow, Scotland, at the global climate conference.

Back home, Tshisekedi has announced that he intends to make Congo “the world capital for strategic minerals.” But some Congolese and U.S. officials think that in order for that to happen, Yuma needs to be ousted.

“We have continuously tried to apply pressure” to have Yuma removed, said one State Department official. Yet Yuma “retains considerable influence,” the official said, baffling the State Department.

Meanwhile, Yuma is carrying on as usual, trailed by an entourage of aides who address him as President Yuma, as he is known throughout much of Congo for his business leadership. It is also a nod to his power base and ambitions.

“I’m a friend of America,” he said in the interview. “I always work in goodwill to protect and to help the U.S. invest in DRC [Congo]. And I told you, I love America. My children were at university there. One of these days, people will understand I’m a real good friend of America and I will continue to help.”

If his success depends on transforming the mining sector, the task will be formidable.