Few events have the power to unite evangelists of religion and science. But the rescue of the 33 miners after 69 days trapped 2,000 feet underground in the San José mine in Chile's remote Atacama desert has touched in equal measure preachers and physicists and, indeed, everyone in between. The global TV audience that watched live as, one by one, these men miraculously emerged from a living hell, has been estimated at over a billion.

For some, the miracle was a traditional one. At 64, grey-haired Mario Gomez was the oldest miner to escape the bowels of the earth. When he stepped out of the Fenix 2 rescue capsule that had carried him to the surface, he fell to his knees in prayer. "I have come back to life," he announced.

For others, the miracle was much more modern and technological. It was human ingenuity that saved these men from certain death, not the divine hand. It was a triumph for the drills that had dug down at speed to the refuge at level 105. And for the cameras that provided the buried miners and their rescuers on the surface with the moral boost of face-to-face contact – and which incidentally also allowed us to watch what once we could only imagine in our nightmares. And, most of all, for the Fenix 2 capsule, just 21 inches in diameter, the most claustrophobic of lifts, designed by Nasa and Chilean navy engineers from a German blueprint.

It was an experiment on the human psyche with us all looking on. These miners, hitherto living tough but anonymous lives in a faraway country, extracting the copper that we take for granted, were suddenly centre-stage when they were at their lowest point.

It was also a test of politicians. Could Chile's good-looking, recently elected TV-mogul president, Sebastian Piñera, and the equally telegenic mining minister, Laurence Golborne, match their fine words and reassuring smiles with the nous to organise the experts to mastermind the greatest of great escapes?

And it was a test of international co-operation. Chile managed both to turn the crisis into a national triumph and to enlist the help of the world. Experts from Nasa flew in to give advice on diet, on technology and on the psychology of those separated by a great natural barrier from the rest of humankind. Sunglasses at $450 (€320) a shot arrived from California to shield the eyes of the miners if and when they saw daylight again, and David Villa, Barcelona's superstar striker, the son and grandson of miners, sent signed football shirts.

Had they met their fate in the initial collapse, as thousands of miners do around the world every year (and an average of 34 annually in Chile), they might have made a footnote in international press. But because they survived, trapped in an air pocket, they drew us all into their lives.

Chile produced 27% of the world's copper in 2009. With demand insatiable in Asia, especially China, prices have been rising steadily, ironically reaching a 27-month high in September just after the world's gaze turned to the Atacama desert. Exports of the metal bring €4bn a month into Chile.

The boom has breathed new life into many old, dilapidated mines such as San José, 500 miles north of Santiago, on a mineral-rich, rainless plateau between the Andes and the Pacific. Safety concerns had been expressed about it, but a job is a job, and €475 a month in wages is sufficient incentive to put such warnings to one side.

Among the shift that went down the steep, zigzagging rampa – or main path – of San José on 5 August were several veteran miners such as Omar Reygadas, a 56-year-old widower and great-grandfather, and Mario Gomez, who had started work underground half a century earlier when he was 12. They were joined by a young Bolivian, 24-year-old Carlos Mamani, a heavy machine operator who had started work there just five days before And by baby-faced 19-year-old Jimmy Sanchez, already the father of a two-month-old daughter but a mining novice with just five months' experience below ground.

At lunchtime, they gathered to eat in the refuge, 2,000 feet down on level 105, when the whole mine shuddered, rocks began to fall and they were engulfed in clouds of dust and grit.

"The most difficult moment," said the shift foreman, 54-year-old Luis Urzua, known as Don Lucho and a key figure in bringing this whole drama to a happy, uplifting end, "came when the air cleared and we saw the rock [blocking the way out]. We knew this was going to be difficult. Suddenly a lot of people tried to do things that were not the best, but luckily we learned to maintain sanity, and thank God there was no accident."

Don Lucho has been credited by his fellow miners with instilling calm and discipline. Supplies were strictly rationed to give them all the best chance. Once every 48 hours, they were each allowed two mouthfuls of tuna, one biscuit and a sip of milk.

Richard Villaroel, the father-to-be, has told one newspaper that, as their food supplies dwindled, the spectre of the survival of the fittest, even of cannibalism, raised its ugly head, albeit unacknowledged. "At that moment, no one talked about it," he said, "but once [help came], it became a topic of joking, but only once it was over, once they found us."

A glimpse of what the men were thinking is provided by the online diary kept by the three children of Omar Reygadas. Since his rescue, his daughter Ximena has reported the conversations the miners had been having. Of those long days of waiting, she writes: "He thought they'd been abandoned and the mining company wasn't going to help them… he thought that once the rations were finished, or when they gave up trying to find them, they would die down there… He prayed to God and asked him that, if he was going to take him, then please would he do it while he was sleeping, so he wouldn't suffer, wouldn't have to live through a landslide."

Temperatures in the refuge were 32 to 34 degrees, and the imagery of hell runs through much of what the miners have said about their prison: "I think I had extraordinary luck," remarked Mario Sepulveda, 40 the second man up. "I was with God and with the Devil. And I reached out for God."

By 12 August things looked bleak. The mining minister told waiting reporters that hopes of finding the missing men alive were "slim". Press attention wavered. It was turning into another tragedy. But the trapped men were hearing, as well as terrifying rumbles that made them fear the earth above them was about to swallow them up, the sound of drills.

It wasn't until 23 August, 17 days after they were trapped and with the rescuers losing heart, that the first of a chain of miracles occurred. The bit of a drill, sent down from the surface, pierced the men's underground chamber. "We all wanted to hug it," Don Lucho recalled. Instead, they sang the national anthem, but then argued as to what return message to attach to it. Finally, all agreed to a simple note scrawled by 48-year-old José Ojeda, who, as the diabetic in the group, was suffering more than most.

"Estamos bien en el refugio los 33." ("All 33 of us are well in the shelter.") The families in the tented village that had grown up around the mine and christened Campo Esperanza – Camp Hope – finally had the sign they had been waiting for. And so did the world's media. Soon there would be as many as 1,500 local and international correspondents and camera crews in the Chilean desert.

On 31 August, eight days after contact had been made, drilling began. In an effort to create, as soon as possible, a shaft big enough, three drills were used simultaneously. If one ran into difficulty, the other two would be well advanced.

After three days, the drills had reached down 120 feet. Just another 1,800 to go. Yet, below ground, discipline and purpose were maintained. The men were split into three work parties. They would sleep in shifts, deal with the food and letters coming up and down the borehole, and clear debris caused by the drilling from above. Conscious that any rescue shaft was going to be a tight fit, the men were encouraged to exercise and get their weight down.

Some have suggested since the rescue that the groups were set up to avoid confrontation; that there had been disputes, even fist fights. But the watching audience saw none of this. There had been bad moments, Don Lucho later said from his hospital bed, but all had pulled together.

On 24 September, a landmark was reached – after 50 days underground, they had broken all records for survival. The drilling too was going better than anyone had expected. On 9 October, there was a breakthrough. The Schramm T130 drill broke through. Engineers decided to encase the first 300 feet in metal to stop loose stones jamming the mechanism of the capsule. The clock was ticking faster.

After four days, they were ready to try the Fenix 2 with a human passenger. The medic, Manuel Gonzalez, and later three more assistants, stayed in the underground chamber to strap in passengers and cope with medical needs, while the first of the miners, Florencio Avalos, 31, began his slow journey to the surface, where he finally emerged in the early hours of last Wednesday.

In less than 24 hours, they had all returned from the dead. Some fell to their knees. Others staggered into the light, bemused and emotional. Others waved their arms in delight. All hugged their loved ones, and a great party got under way, not just in Chile, but all over the world. "What started as a tragedy," said President Piñera, on hand to greet every returnee with a hug, "ends in a blessing".