The Chinese used open caste mine to mine for tin in Malysia in...

The Chinese used open caste mine to mine for tin in Malysia in the 50s and 60s. The cost was cheap that was a couple of hundred grands, using timber frames. They build a sliding frame with steps and earth and sand were washed down this open frame structure. The heavier tin stayed behind whilst sand and earth were washed down to a tilings at the end of the slide.The same principle could apply to gold.This is the next step up from pan mining and very cost effective, especially when capital reserves are low and the process is very profitable.The British were using dredges those days which was capital intensive, costly and they used enginners. The Chinese used mainly laborers and they got the job done just the same. The gold could be mine cheaply in Mali too.