Prospector Trails
Stories/Copper and cobalt · DR Congo
In Katanga, copper was cast into crosses and used as money long before any company arrived. In the 20th century the same ground supplied copper to the world and uranium to the first atomic bombs. Today it supplies most of the cobalt in the world's batteries.
01 · Copper country
Katanga's copper was smelted and cast into X-shaped crosses long before Europeans arrived, and the crosses were traded as money across central Africa.
In 1906, under King Leopold II's Congo Free State, Union Minière du Haut-Katanga was founded to mine the copper around today's Lubumbashi and Kolwezi. Railways, smelters and company towns followed.
Sources: Katanga Cross; University of Liège.
02 · The uranium
Uranium was found at Shinkolobwe in 1915, and its ore was unusually rich. In 1940, fearing a German invasion of Belgium, Union Minière's head Edgar Sengier shipped about 1,200 tonnes of it to a warehouse on Staten Island.
In September 1942 a US Army officer came to ask about Congolese uranium. Sengier's reply became famous: "You can have the ore now. It is in New York, a thousand tons of it." It went into the Manhattan Project.
Sources: Atomic Heritage Foundation; Shinkolobwe.
03 · Independence
The Congo became independent on 30 June 1960. Katanga, home of the mines, broke away for two and a half years, with Union Minière's backing, before the secession ended in 1963.
In 1966 the government took over Union Minière's Congolese mines. The state company, later named Gécamines, ran the Copperbelt for decades, until output collapsed in the early 1990s.
Sources: Union Minière; Gécamines.
04 · The cobalt century
Katanga's copper ores also carry cobalt. For most of the 20th century it went into alloys, magnets and blue pigment. Then lithium-ion batteries arrived, and demand climbed.
World cobalt mine output rose from about 180 tonnes in 1901 to about 302,000 tonnes in 2024. The Congo mined about 226,000 tonnes of it, about 75%. Indonesia, mining cobalt with nickel, is now second.
Data: USGS MCS 2026 and DS140.
Cobalt: where it is mined and traded05 · Two kinds of mine
Around Kolwezi, large industrial pits with haul trucks and processing plants sit next to artisanal diggings, where miners work by hand in pits and tunnels and sell ore to traders.
Unsafe conditions and child labour in artisanal mining have drawn international criticism. Many battery makers and carmakers now try to trace their cobalt back to the mine.
Source: Cobalt mining in the DR Congo.
06 · Where it goes
The Congo is also the world's second-largest copper miner, with 13.9% of world output in 2025. In 2024 it shipped about $13.7bn of refined copper cathode to China.
Cobalt leaves mostly as hydroxide and other intermediates, and most of it is refined in China into battery chemicals.
Trade: CEPII BACI. Shares: USGS.
Mining in the DR Congo07 · The gate closes
After cobalt prices fell sharply, the Congo suspended cobalt exports on 22 February 2025. From 16 October 2025 exports restarted under quotas, set at 96,600 tonnes a year for 2026 and 2027.
For a metal with one dominant source, a single government decision now moves the whole market.
Sources: IEA: export suspension; IEA: quota system.
Critical minerals explainedThe full story
The Copperbelt of Katanga, in the south of the Democratic Republic of the Congo, is one of the richest mineral regions on Earth. Its history runs from pre-colonial copper money through colonial mining, the atomic age and independence to today's battery supply chains.
Copper was smelted in Katanga for centuries and cast into X-shaped ingots known as Katanga crosses. They were used as currency across the region, for bride wealth and for trade, into the early 20th century.
Union Minière du Haut-Katanga was founded in 1906 to mine Katanga's copper. It built mines, smelters and company towns around Élisabethville (now Lubumbashi) and Kolwezi, and became one of the world's largest copper producers.
Uranium was found at Shinkolobwe in 1915. In 1940 Union Minière's director Edgar Sengier had about 1,200 tonnes of uranium ore shipped to New York and stored on Staten Island. When the US Army's Kenneth Nichols met him in September 1942, Sengier told him the ore was already in New York, and the Army bought it for the Manhattan Project.
The Congo became independent on 30 June 1960, and Katanga seceded until 1963. In 1966 the government took over Union Minière's Congolese assets, which became the state company later named Gécamines. Its production fell steeply in the early 1990s, and since the 2000s most of the Copperbelt's output has come from joint ventures and private companies.
Cobalt occurs with Katanga's copper. With the growth of lithium-ion batteries, the Congo's share of world cobalt mine output reached about 75% in 2024: about 226,000 tonnes out of 302,000 (USGS). Indonesia, which produces cobalt from nickel laterites, is the second producer. Artisanal miners produce part of the Congo's cobalt, and conditions in artisanal mining, including child labour, remain a major concern.
The Congo suspended cobalt exports on 22 February 2025, after prices fell. On 16 October 2025 a quota system replaced the suspension, with 96,600 tonnes a year allowed for 2026 and 2027 (IEA policy database).
A Katanga cross is an X-shaped ingot of cast copper, used as currency in the Katanga region in the 19th and early 20th centuries. A typical cross weighs about a kilogram.
Yes. Uranium ore from the Shinkolobwe mine in Katanga was a major source for the Manhattan Project. In 1940 Edgar Sengier of Union Minière shipped about 1,200 tonnes of ore to a warehouse on Staten Island, and the US Army bought it in 1942.
In 2024 the Democratic Republic of the Congo mined about 226,000 tonnes of cobalt, out of a world total of about 302,000 tonnes, or about 75% (USGS Mineral Commodity Summaries 2026). Most cobalt is a by-product of copper mining.
To support prices after a sharp fall, the Congo suspended cobalt exports on 22 February 2025. From 16 October 2025 exports resumed under quotas, set at 96,600 tonnes a year for 2026 and 2027 (IEA policy database).
Artisanal miners dig by hand, often in unsafe pits and tunnels, and sell ore to traders. Working conditions and child labour in artisanal mining have drawn international criticism, and many buyers now try to trace where their cobalt comes from.
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Photos from Wikimedia Commons: The Big Hole by Rudolph Botha, CC BY-SA 3.0; Super Pit, Kalgoorlie by Kgbo, CC BY-SA 4.0; Cerro Rico over Potosí by Jbmurray, CC BY-SA 4.0; Chuquicamata from the ISS by Alexander Gerst (ESA), CC BY-SA 2.0.