Issue 12
Words by

The discovery of copper

7th September 2023
19 Mins

Today’s world requires vastly more copper than you could imagine, and the world of electric vehicles will require even more. That means finding new ways to find and extract copper from the earth’s crust and oceans.

In 1983, the 29-year-old Steve Jobs bought a rambling old mansion in Woodside, a quiet, wealthy little Californian town midway between San Francisco and San Jose.

The property was hardly the obvious choice for a young entrepreneur. Surrounded by six acres of encroaching forest, the dilapidated house was enormous – 30 rooms, 14 bedrooms and 13 and a half bathrooms – and was filled with odd trinkets, including a fully-functioning pipe organ.

The Apple cofounder lived there for around a decade but never actually got round to furnishing it. He would eat meals on the bare floor and sleep on a bare mattress. One girlfriend found the place so spooky she refused to live there. Eventually Jobs moved out, into a smaller, more manageable place down in Palo Alto. But the Jackling House, as it was known, would continue to haunt him, one way or another, for the rest of his life.

The house was named after the man for whom it was originally built, a fellow called Daniel C. Jackling. Don’t worry if you haven’t heard of him: he is mostly forgotten these days, but Jackling’s legacy is arguably even greater than that of the man who brought us the Mac and the iPhone.

If we have been living in Steve Jobs’ world of computers and devices for a decade or so then we have been inhabiting Jackling’s world for a century or so. Yet since Jackling was a creature of what I like to call the ‘Material World’ – the unappreciated underbelly of modern life – his contribution to our lives is enormously neglected, despite the fact that it is there in the fabric of nearly everything we touch. Jobs used to describe Jackling as a ‘copper baron’, but that was understating it, for he might better be seen as a modern-day alchemist. He was the man who transformed the job of turning rock into metal.

Up until recently it has been quite easy to forget how important copper is to the modern world. Perhaps that’s because unlike the other foundational components of civilisation like steel or concrete, copper is invariably sheathed away from view inside wiring. Yet without copper there would have been no electrical age – no second Industrial Revolution. Indeed, for a period in the late nineteenth century it looked worryingly as if the electrical era would halt before it began, because of a shortage of the red metal.

Up until the late nineteenth century, most of the world’s copper was mined and sorted more or less manually. Chunks of rock were torn away from the ground and inspected to check whether they had the tell-tale signs of copper (sometimes the green of oxidised copper, sometimes a yellow crystalline mineral known as chalcopyrite). High-grade ores with more than a few percentage points of copper were sent off for smelting and processing and the rest was left in the ground.

The problem was, by the turn of the twentieth century the most abundant ores had already been mined out. So, as the electrical age dawned, global copper production was flatlining. Even as he was inventing some of the world’s first lightbulbs and building the world’s first power stations, Thomas Edison was fretting about being able to lay his hands on enough copper to put inside them.

That brings us back to Jackling, a self-made man who came from poverty but managed to get himself trained as a mining engineer. What if, Jackling asked himself, you could extract copper not just out of those high-grade chunks (copper content of over five per cent) but also out of the other stuff too? In many mines around the world there were vast volumes of ores which looked to the untrained eye like normal rocks but contained a few percentage points of copper. They were set aside because it was simply too expensive to justify refining them. But, wondered Jackling, might there be some way of changing the calculus?

In 1904 at Bingham Canyon, just outside Salt Lake City, Utah, he answered that question in dramatic fashion. Vast quantities of explosives were deployed to blast massive chunks of low-grade ore out of the ground. Steam shovels and steam crushers were brought in to ferry and grind the ores. What was once a mountain was turned into a kind of dust, which was then mechanically and chemically processed in what became known as ‘flotation separation’: the ore dust was mixed with an oily compound and then sloshed and shaken inside large tanks, allowing copper particles to float to the surface before being smelted into solid metal.

What might sound like an arcane set of process changes turned out to be utterly revolutionary. Jackling’s ‘non-selective techniques’, as they are sometimes called, meant you could extract copper from even low-grade ores in large quantities. All of a sudden, the metal was no longer in short supply; it was plentiful. Better still, new electrolytic refining methods meant that the quality of copper being turned out by these new mega-mines was even better than the kind previously produced by older reverberatory furnaces, which roasted processed copper ores and dominated the business back in the nineteenth century, when the UK refined most of the world’s metals. That mattered because only the very purest copper could be turned into wires for generating and conducting electricity. At the very moment the world needed ultra-pure copper in large quantities, Jackling and his financiers, including the wealthy Guggenheim family, helped deliver it.

The electrical age, in other words, was not just the product of inventors and entrepreneurs like Edison, Nikola Tesla and George Westinghouse – it was thanks just as much to forgotten figures like Daniel C. Jackling. Even as Henry Ford was revolutionising mass production in Detroit, Jackling was doing much the same thing for mining, turning a small-scale industry into something enormous and vastly increasing its output in the process. 

But there was a darker side to his innovation. What it meant in practice was that rather than burrowing into a mountain, following a rich seam of ore deep into the earth, miners would now essentially demolish the entire mountain to extract its metal. This was not just mass production, but ‘mass destruction’. The world got the copper it needed for the electrical era, but only thanks to the obliteration of landscapes like Bingham Canyon. Today Bingham Canyon is more than four kilometers long, two and a half kilometers wide and a kilometer deep. While it is a relatively small mine in output terms these days, it still produces staggering amounts of copper – more in a single year than the entire world produced each year before Jackling came along. 

An early photograph of the Bingham Canyon copper mine
From Wikimedia

The hole

But while some claim Bingham is the biggest man-made hole in the world, there is another copper mine in Chile which beats it to the line. Chuquicamata, which opened in earnest a few years after Bingham Canyon, is probably the most important mine to use Jackling’s methods. This site, high up in the Atacama Desert, has produced more copper than any other place on earth. Roughly one in 14 of every atom of copper ever mined came from this place, of which few have heard, let alone visited. There’s a good bet there’s some Chuquicamata copper in the device on which you’re reading this, but since we don’t pay all that much attention to copper and where it comes from, most people are none the wiser.

The scale of the place has to be seen to be believed. Surveying the hole reminded me of the first time I had seen the Grand Canyon, only the Chuquicamata is entirely man-made, carved out not by rivers and rain but by dynamite and diggers. It is a testament to the kind of mining Jackling pioneered, and once you have seen this sight it is hard to look at any of your electronic devices, or for that matter to flip a light switch, in the same way again. For they are all indirectly responsible for great holes in the earth like this one.

Among those who were left with a lasting impression after having seen Chuquicamata was South American revolutionary Che Guevara. ‘You cannot say that it’s lacking in beauty,’ he wrote after visiting it in 1952, ‘but it is a beauty without grace, imposing and glacial.’ Every morning, he continued, ‘the mountain is dynamited and huge mechanical shovels load the material to rail wagons.’. What he was describing was the legacy of Daniel C. Jackling. He was describing the mineral underbelly upon which all modern technology rests.

Copper mining in Chuquicamata is still done in much the same way even today. Enormous chunks of rock are blasted out, ground down into a dust as fine as face powder and separated in flotation tanks much as happened in Jackling’s day. Then these concentrated ores undergo further pummelling and processing. They are smelted and then ground down again, each time becoming ever more pure. The final step involves a form of electrolysis: 98.6 percent pure copper slabs are dunked in tanks containing an acidic solution, where they sit for nearly two weeks while an electric current is run through them. What you end up with – after the metal atoms in the anode, the slab you started with, have migrated across to the cathodes – is a sheet of 99.9 percent pure copper. 

These copper cathodes (and some of the less pure concentrate) are then carried down from the highlands of Chile to the Pacific on a hundred-year-old railroad. But even though Jackling set the template for modern mining, replacing old underground mines with enormous open pit operations in America, Chile, the Democratic Republic of Congo and beyond, things have come a long way since he retired and lived out his final days in that mansion in the California hills.

In the succeeding decades, the trucks that transport the ore have become far bigger, the machines crushing the rocks far more efficient. There are now new, improved techniques to refine copper from the ore, allowing modern day miners to extract ever more metal from ever less promising rocks. The average grades of copper ore carried on falling in the succeeding years: from 2.4 percent in 1913 to down below 2 percent by the middle of the century and below 1 percent by its end. But this came at a cost: as the grades fell, the task of extracting copper from the ores became significantly more demanding. Between 1900 and today, the quantity of stone needed to move and process to produce a single tonne of copper rose from 50 tonnes to 800 tonnes. The amount of water consumed along the way went from 75 cubic meters to 150. The energy needed for all this work rose from around 250 kWh to over 4,000 kWh.

Given all of the above perhaps it’s unsurprising that there have been periodic scares that the world is about to run short of copper. There were scares at the turn of the twentieth century, scares in the 1970s – with the Club of Rome, an influential environmental institution, warning that we were close to exhausting the global supply of this metal – and scares in recent years, too. Yet here’s the striking thing: not only have we carried on mining copper, gradually increasing the annual amount coming out of the ground; but the price of the metal has only risen in line with inflation, the basket of typical household goods and services. On this basis, the ‘cost’ of copper is broadly similar to what it was decades ago.

The more you think about this the more extraordinary an achievement it is. The twentieth century’s electrical era was built out of copper – a great tide of copper for the electrification of major cities, the age of consumer electronics and the rise of mammoth new markets for wiring and electronics like China and India. Even as people demanded more copper, the earth became considerably less willing to give it up. Yet somehow those working in Chuquicamata and elsewhere kept churning out copper at pretty much the same price. Falling supply; rising demand. You might have thought the price should have headed skyward, potentially stifling the world’s progress – but no.

Indeed, in recent decades we have also increased the quantity of reserves left in the ground – not merely by finding more copper ore in the ground, but by changing the definition of what constitutes an accessible copper ore. It comes back the trend Jackling began: in much the same way as he deployed ‘mass destruction’ to turn hitherto waste rock into copper, we are still grinding our way down the percentage scale, recategorizing ever lower-grades of ore as promising rock. Meanwhile, we are getting ever better at weaning out other metals from the same rocks: cobalt and molybdenum, nickel and gold.

It’s worth taking a moment to ponder this, for it amounts to one of the most remarkable stories of the modern world. Steve Jobs was intimately acquainted with the theory of Moore’s Law, whereby each couple of years the transistor density of semiconductors would double. This exponential increase has resulted in transistors shrinking from being measured in millimeters to being measured in nanometers, and computing power which costs infinitesimally less. In the past decade alone the price of solid state memory chips fell from around $1,000 per terabyte to less than $50 per terabyte. 

Something similar has happened in the copper mines of Utah and Chile – but this version of Moore’s Law is rarely ever discussed. According to mining expert Paul Gait, if you look at the number of labour hours it takes to mine and refine a tonne of copper, it has fallen rapidly and consistently over much of civilised history. At the time of the Roman Empire the price of a tonne of pure copper was equivalent to roughly 40 years of the average wage: forty years of work. By 1800 this had fallen to six years per tonne. In the following 200 years to the early twenty-first century it dropped to just 0.06 years (or 21 days) per tonne.

It is this phenomenon which has ensured we never ran out of copper. Even as the world’s population swelled to eight billion, the supply of copper remained more or less sufficient. We just got better and more efficient at getting it out of the ground. Bigger trucks, bigger machines, better chemicals. Fewer mineworkers blasting, shifting and grinding more tonnes of ore.

It is, depending on how you look at it, a productivity miracle or an environmental disaster. In practice, it’s a bit of both, as getting better at getting copper out of the ground also involved blasting ever bigger holes in the ground. This process generates enormous waste, from the rocks blasted out of the ground which had too little ore to process, through to the ‘tailings’ left behind after the copper ores have been processed – a toxic stew which used to be dumped into the sea. There is evidence that the health of those living near mines and refineries, not to mention those rivers and coastlines which once served as dumps for the waste, has been beset. These days the tailings are stored behind earthen dam walls. In Chuquicamata, the tailings dam containing all the waste material now covers an area bigger than Manhattan.

The piles of waste rocks discarded because they didn’t have enough copper are now so big that they have engulfed the local village that once housed all the mining workers. The town has been abandoned, partly because it was getting in the way, partly because the toxic fumes puffed out of the refinery were judged to be a risk to the children living there. What was once South America’s most advanced hospital is now buried under tonnes of rubble. You could hardly ask for a better illustration of what it takes to provide the rest of the world with the raw materials it needs.

A new age of copper

But we’ve only just begun, because our copper needs are set to multiply in the coming decades. After all, the primary way we’ll eliminate carbon emissions is by electrifying more or less everything, from the way we heat our homes to the way we propel our cars. And that means much, much more copper.

The average internal combustion engine car contains about a mile of copper wire. The average electric car contains three or four times more. Then there’s the many tonnes of copper we will need for all the wind turbines, solar panels and other grid infrastructure you need if you’re relying ever more on power – copper for the circuitry inside them, for the windings in generators and transformers and, most of all, for the thick, shielded cabling taking power from one place to another.

All told, according to some estimates the green energy transition will necessitate us doubling the total amount of copper we use each year from around 25 million to more than 50 million tonnes. Those numbers might seem somewhat meaningless on their own, but here’s another way of putting it into perspective. Even if we dramatically improved our recycling rates, it would still mean opening another three megamines like Chuquicamata or Bingham Canyon (the world’s biggest man made holes!) every year. Three of them. Every single year!

If that sounds implausible then that’s because it probably is. Look ahead at the pipeline of impending new copper mines and while there are one or two big ones planned in the coming decades, there is nothing like what we need. The very countries where there is the most identified available copper, places like Chile and Peru, are becoming ever more reluctant to approve new mines. For decades Western businesses have been able to rely on a more or less constant stream of copper coming from these big holes in the ground, miles from human habitation, but now those in charge of the holes are having second thoughts.

Even copper optimists are now quite worried about this. In theory a potential shortage of demand should spark new supply. That's what happened in the past, after all. But while we never ran out of copper in the late nineteenth or early twentieth century, that's not to say it was exactly plain sailing. It relied on hard work, some clever innovations on refining and, most of all, our willingness to dig ever deeper holes. Can we repeat that? Possibly. But getting there may entail a few nervy decades in which it really does feel as if we're running out of the metal. 

Already, miners are going to ever greater lengths to find new supplies of copper. Some are considering deep sea mining, though that comes with a host of its own environmental challenges, to put it mildly. Others are trying to do deals in countries with more volatile political histories. But perhaps the most likely way we’ll ensure we have enough copper is to summon up the spirit of Daniel C. Jackling all over again – coming up with new ways of squeezing more metal out of ever less concentrated ores.

The latest thing in copper exploitation is actually a novel form of underground mining, where you blast out massive chunks of the earth from deep in its bowels, rather than using drills as they do in most underground mines. They call it block caving. Right now Codelco, the company which owns and runs the mine at Chuquicamata, is burrowing one of these block cave mines directly under the deepest hole in the world. 

Meanwhile, others are seeking out new chemical techniques which might help them squeeze metal out of what is currently regarded as waste ore, with less than 0.5 percent copper. That, after all, was the trick Jackling pulled off over a century ago, setting us on track for the modern era of electronics and mass urbanisation. The man himself may be mostly forgotten today, but his legacy still lives on – in the shape and scale of mining techniques still used today.

As for the Jackling House, that too is now little more than a memory. After he moved out, Steve Jobs rented out the old mansion in Woodside for a bit, but then decided he wanted it pulled down and replaced with a modernist Japanese-inspired building. Local campaigners objected. This, they said, was a historic monument, one of the best examples of the Spanish colonial revival style. The 1990s wore into the 2000s. Jobs masterminded the return of Apple from corporate irrelevance to become one of the world’s most important companies.

Even so, he still couldn’t persuade the local authorities to allow him to demolish the spooky old Jackling House. So he allowed it to sit there, festering and decaying. The old pipe organ sprouted weeds. The remnants of Jackling’s memory – the trinkets from copper mines and insignias from the businesses he led – gathered dust. Eventually, in early 2011, Jobs finally got permission to raze the house, but by then he was engaged in another battle, this time with cancer. He died later in the year.

Today the mansion is no longer there. Laurene Powell Jobs, Steve’s widow, finally removed it and built the dream home her husband never managed to. The footprint of the old mansion is now occupied by a vineyard. Today it is to Jobs’ memory that many people turn when they think of the key figures of the electronic age. But none of his achievements, extraordinary as they were, would have been possible without those of the man whose home he never quite managed to destroy.

More articles from this issue

Making architecture easy

Words by Samuel Hughes

Unlike nearly all other arts, architecture is inherently public and shared. That means that buildings should be designed to be agreeable – easy to like – not to be unpopular works of genius.

Read more