In this small community in the foothills of the eastern Andes mountains, multinational mining company Esmeraldas Mining Services deposits tons of earth it has processed from its operations into a cage-like enclosure.

A few times a month, the mining company allows hundreds of miners — known as "guaqueros" or treasure hunters — to search through the detritus and take home any precious stones they find.

Emerald hunters come to Muzo, a town of about 9,000 inhabitants about 200 kilometers north of the capital Bogota, from all over South America.

Among the miners is Miguel Hernandez, 72, who grips a cane as he waits outside the cage, where some hopefuls have lined up since 3 am.

"May our Heavenly Father give me a gift so I can buy a new home …it's what I want most," he said.