If the material drops down out of the hopper too fast, it can overwhelm the riffles and you can blow the gold right out. If it runs too slowly, the riffles can clog up and the process is too slow.

…in spite of the fact that the well-pounded spots probably don’t have much gold left, I see all too many prospectors hike down to a creek or other spot at the first place the road comes near it just because it’s the easiest access point.

The area was mined intermittently from around 1900 to 1915, but was also mined in the late 1800s, with a total output valued at about $100,000, which is around $9.5 million at the current gold price.