Common thought is the switchback slows the velocity of the rushing water and gold drops out from the cut bank to a fill gravel bar within or below the switchback. I am not going to disregard that model; however, I hope to improve upon it.

Because tungsten minerals are heavy, exploration can be done using stream sediment samples. Prospectors looking for gold have found scheelite or wolframite in their placer concentrates, and in some cases this has led them to make important tungsten finds.

This mine was a real wonder of engineering, and the water supply and drifts had to be carefully managed to keep it in operation. In fact, it didn’t close due to lack of gold, but instead closed with the fall of the Roman Empire.