Editor's note: In the times of the Spanish Empire, the mines of Zaruma, 80 miles southwest of Cuenca, were one of the crown's major producers of gold and silver. The production, over a 250 year period, came at the cost of an estimated 10,000 lives, many of them enslaved Cañari people from the Cuenca area. Today, heavy mining has moved on to richer veins but small "artisanal" miners continue to work the shafts and pits, scratching out meager livings. BBC reporer Leo Johnson reports on their lives.
By Leo Johnson
In Zaruma, southern Ecuador, gold has been exploited for more than 500 years. Today, some 10,000 people in and around Zaruma still live off "artisanal" mining. For One Square Mile, Leo Johnson visited one such mine to witness the challenges miners face.
It's pitch black. I am 120 metres underground and there's a smell of blood.
The Canari Indians died here, deep in the gold tunnels of Ecuador's Andes. First the Incas, then the Conquistadores, working the Indians till they dropped.
"Get me gold," demanded Philip II, Spain's 16th Century king.
"Humanely, if possible, but get me gold."
So old blood, there's plenty. But this smells fresh. It's got the tang of iron.
I nose towards the scent, and there, glinting in the flame of my miner's lamp, hanging from the ceiling, is a bulbous red and orange mass. It is rusting iron, an outcrop of hematite, natural iron ore, rusting with the water that's dripping from it.
A local miner emerges out of the shadows.
"Bueno," he says, "food for El Duende."
El Duende. There's no word for it in English.
For Federico Garcia Lorca, the Spanish poet, it's the power that "surges up, inside, from the soles of the feet", the power that tells the bullfighter when and how to plunge the knife, that makes us cry at the performance of flamenco.
It is the unuttered cry that marks the triumph of truth over lies.
For the miners of Zaruma, El Duende is also a being, a primitive force from the core of the Earth.
How do you know you've found gold?
El Duende, invisible, throws pebbles that send shivers down your spine. So rusting iron in the tunnel, El Duende's favourite food, means one thing. He's close. Gold's close. Your luck might just be in.
And the team I am with are in need of luck.
Fabian Samaniego, 39 years old, has been working this hill since he was 14. Two years ago he took his life savings and gambled them here, in Zaruma's "Hill of Gold".
But the gold dried up for him. Time's running out for Fabian.
This is a job where things can go wrong. Earthquakes, mine collapses, explosions.
But even when it goes right, it's not good for the lungs or back.
Want to fill a sack with $10 (£6.50; 7.70 euros) worth of gold?
You have got to hammer out about 30kg of rock in the dark, bag it up, heave it on to your back and haul it out. I filled one. It was hard. Fabian has clocked up 50 bags a day, six days a week on average, for 25 years.
But the real problem for Fabian isn't inside the mine, it's outside. It is the competition.
Ecuador's dilemma is this. With more than a quarter of the country living below the poverty line, it is sitting on more than $200bn worth of gold, copper and silver alone.
Rafael Correa, Ecuador's left wing president, has a strategy to develop by extracting the resources.
"We can't be like beggars sitting on a sack of gold," he has said.
And it's foreign mining companies, Chinese and Canadian, with the capital and technology, that are winning the concessions.
Across Ecuador, indigenous groups have protested.
The Shuar, one of the groups, have marched to Quito, threatening conflict. And there are early signs of possible social tension around Zaruma.
In the early hours of 23 July last year, four cars pulled up at the gates of Dynasty Metals, the Canadian company now mining for gold around Zaruma.
Twenty people, dressed as police and priests, came to the gate, pulled out sub-machine guns, then made off with an estimated $2m of gold.
Whether this was robbery or restitution, an isolated incident or a local community response to the ongoing removal of Ecuador's gold, it's too early to tell.
For pessimists, there's the risk of a stalemate. The concessions get awarded to foreign companies, but social unrest grinds production and Ecuador's development to a halt.
For optimists, there's another route.
Local businesses, like Fabian's, get enough capital and technology in place to compete for concessions. Smaller scale, not giant, but mercury free, and with money that stays in the community.
But that depends on one thing happening. Local miners like Fabian have got to find gold to get the capital to invest.
Back underground, the mine's gone quiet. The tunnels above and below us have been cleared.
"Dynamite time", Fabian tells me.
I follow him, bent almost double, until the tunnel ends. Eleven black plastic fuses are sticking out of the wall. He strips them, exposing the cord, then passes me the flame to light the sticks of dynamite.
"Don't worry", he says, "it is finest quality. Bolivian."
I light the fuses. The last are the hardest.
You know what I want to say to the Bolivian dynamite industry?
You are craftsmen. You are men, and women, who make no mistakes. Bang on time, 180 seconds later, at the entrance to the tunnel we hear the whoomps, muffled, like a distant lid closing on a biscuit tin.
It is the sound of a new vein of gold maybe opening up for Fabian, and a different possible future for Zaruma.
Later that night there is a cultural festival.
As a visiting Englishman, I am given both an honour and a bit of a challenge.
I am called to the stage and presented by the mayor of Zaruma, in front of the whole town, with a magnificent portrait of Queen Elizabeth II.
"It is for you", he tells me, "to take back to the Queen."
Surging up, from the soles of my feet, I feel what must be El Duende.
"No problem", I assure the crowd.
Credit: BBC News, www.bbc.co.uk/news/world-radio-and-tv-22718928; Photo caption: Reporter Leo Johnson prepares to go into the mine.