A long trough with ridges along the bottom. Gravel mixed with water washes over the ridges. The heavier gold is trapped in the ridges and the water and lighter gravel fall out of the end of the sluice. See Yellow Eagle Mine, Alaska Gold Dredges, or Sluicing and My Dad.

A modified rocker. Water power forced dirt through the box, a sloping trough or inclined flume, and heavy gold-bearing particles were caught by riffles or slats. Mercury (quicksilver) was sometimes placed behind the riffles to catch the gold. Hydraulic mining used a long series of sluices.

a long, narrow, sloping box with riffles placed at intervals to catch gold while the lighter sand and gravel are washed through by water