Prospector Trails
Stories/Copper · Utah and Chile
A hundred years ago engineers bet that they could make money from rock with less than 2% copper, if they moved enough of it. They were right. The pits they started in Utah and Chile are now among the largest holes people have ever dug, and copper has become the metal of electricity.
01 · Bench by bench
In 1906 Utah Copper began mining Bingham Canyon as an open pit, with steam shovels and railways. The rock held well under 2% copper, but moving huge volumes made it pay. It was one of the first mines built on that idea.
The pit now measures about 4 km across and more than 1.2 km deep. It has produced more than 19 million short tons of copper, more than any other mine.
Sources: Bingham Canyon Mine; Mining Technology.
02 · The slide
On the evening of 10 April 2013 the north-east wall of the pit collapsed in two slides, about 90 minutes apart. Around 165 million short tons of rock poured into the bottom of the pit. Researchers called it the largest non-volcanic landslide in the modern history of North America.
Slope radar had picked up the wall creeping for months, and the mine had moved people and equipment away. Nobody was hurt.
Source: GSA Today (2014).
03 · The desert giant
In Chile's Atacama Desert, Chuquicamata has been mined on an industrial scale since 1915. Its pit is about 5 km long, 3 km wide and about 1 km deep, one of the largest open pits in the world.
At that depth, hauling rock up the ramps cost too much. In 2019 Codelco started mining it from below, with tunnels and block caving under the old pit.
Sources: Codelco; Chuquicamata.
04 · To scale
Side by side: Bingham Canyon, Chuquicamata, Kimberley's Big Hole (about 460 m across, dug by hand) and the Eiffel Tower (330 m).
The Big Hole, once the largest hand-dug excavation, would fit many times over in either copper pit.
Sizes from the sources above and the Kimberley story.
05 · A century of copper
World copper mine output was about 495,000 tonnes in 1900. By 2025 it was about 23 million tonnes, 46 times more, as electricity, cars and buildings spread.
Chile mined about 23% of the world's copper in 2025, the Democratic Republic of the Congo 13.9% and Peru 11.7%.
Data: USGS DS140 and MCS 2026.
06 · Where copper goes
Most copper leaves the mine as concentrate, typically 25–30% copper, and is smelted elsewhere. In 2024 Chile shipped about $20.8bn of copper ore and concentrate to China, the largest single flow of the trade.
The arcs show the biggest ore and refined copper flows: from Chile and Peru, and cathode from the Congo, mostly to China.
Trade: CEPII BACI, HS 2603 and 7403.
Copper: where it is mined and traded07 · Copper is electricity
Grids, motors, chargers, wind turbines and electric cars all need copper. Many governments now list it as a critical or strategic mineral.
Bingham and Chuquicamata took decades to grow. The deposits that will feed the 2040s are being found and drilled by exploration companies today, and it can take well over a decade to go from discovery to production.
Which minerals are critical, and to whomThe full story
Open-pit copper mining was an engineering bet: that low-grade rock, with well under 2% copper, could be mined at a profit if enough of it was moved cheaply. Bingham Canyon in Utah and Chuquicamata in Chile proved the bet, and their pits grew into some of the largest excavations on Earth.
Claims were staked at Bingham Canyon in 1863, but the open pit dates from 1906, when Utah Copper began mining with steam shovels. Today the pit is about 4 km wide and more than 1.2 km deep, and the mine has produced more than 19 million short tons of copper, more than any other mine in history. It also produces gold, silver and molybdenum.
On the evening of 10 April 2013 the north-east wall of the Bingham pit failed in two slides. About 165 million short tons of rock moved, in what researchers writing in GSA Today described as the largest non-volcanic landslide in the modern history of North America. Ground radar had detected the movement, the mine had been warned, and no one was injured, though trucks and shovels were buried. The slide is now a standard case study in slope monitoring.
Chuquicamata in the Atacama Desert has been mined on an industrial scale since 1915 and has been run by the state company Codelco since the 1970s. Its pit is about 5 km long, 3 km wide and about 1 km deep. Because deeper open-pit mining had become too costly, the mine began its move underground in 2019.
World copper mine production rose from about 495,000 tonnes in 1900 to about 23 million tonnes in 2025 (USGS). Chile is the largest producer, followed by the Democratic Republic of the Congo and Peru. Most mined copper is shipped as concentrate to smelters, and China is the largest importer of both concentrate and refined copper.
The Bingham Canyon pit in Utah is about 4 km wide and more than 1.2 km deep. It has been mined as an open pit since 1906 and has produced more than 19 million short tons of copper, more than any other mine.
On the evening of 10 April 2013 the north-east wall of the pit failed in two slides, now called the Manefay slide. About 165 million short tons of rock moved. Radar monitoring had detected the movement in advance and the pit was evacuated, so nobody was hurt.
Chuquicamata, in Chile's Atacama Desert, has been mined on a large scale since 1915. Its open pit is about 5 km long, 3 km wide and about 1 km deep. In 2019 Codelco began moving the mine underground.
About 23 million tonnes of copper in 2025, up from about half a million tonnes in 1900 (USGS). Chile produced about 23%, the Democratic Republic of the Congo 13.9% and Peru 11.7%.
Copper carries electricity in grids, motors, chargers, wind turbines and electric vehicles. Many governments now list it as critical or strategic because demand from electrification is rising while new mines take many years to build.
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1545–2026Silver · BoliviaOne red mountain in the Andes fed the first global trade, through forced labour and mercury. Next door lies a salt flat full of lithium.
1906–2026Copper and cobalt · DR CongoCopper crosses used as money, the uranium in a New York warehouse, and the country that now mines three-quarters of the world's cobalt.
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; Malachite on cobaltocalcite, Musonoi by Ji-Elle, CC BY-SA 3.0.