In the jungles of North Cambodia, whole families follow the semi-precious stone lines with their tents in the hope of finding something. But the yield is small and they are just the start of the supply chain anyway.
In the tropical heat they dig vertical tunnels wide enough for one person and up to 10 metres deep in the ground. Then they connect them together which often leads to the tunnels collapsing and even people being killed. From the youngest upwards, everyone spends the day looking through the earth. The proceeds are enough for the food that will enable them dig further the next day.