Finding a diamond in a river seems like a charming, but implausible, tale from an old adventure book, but in Sierra Leone this is exactly what is happening.

Dr Laurent Cartier, a gemmologist, lecturer and sustainability expert, travelled to the African country to create a short film about the diamond divers of the Sewa river. Here, men do not dig for diamonds but dive, sometimes up to 10m in depth, with zero visibility, to fill buckets of silt by hand in the hope a diamond will be uncovered.

“Working here in 1978, sometimes you could find 100 diamonds per day,” says Umaru, a 47-year-old diver, who has spent more than two decades in search of Sewa river diamonds.

Yet things have changed in the Sewa river. As Cartier points out, diving for diamonds in the river today is “much more of a lottery”.

Despite this, Umaru says he prefers this way of life to the alternative of mining for gold, another of Sierra Leone’s industries. “Diamond[s], you try for 10 years and then one day you can become a millionaire,” he says.

Then comes the challenge of holding on to that wealth in a country that has struggled with corruption and poverty in the aftermath of its decade-long civil war. Sierra Leone was, of course, once synonymous with blood diamonds.

“It is extremely rare in this world to dive for a diamond rather than to dig for it,” says Cartier. “Since I first met these divers in 2007, I have been impressed and inspired by their hard work, hope and sense of pride.”

You can watch the nine-minute film, The Divers of Sewa, below.