Drywasher - A mechanical apparatus used for separating free particles of placer gold from dry sediments.
This absence of water directly correlates to the low moisture content of alluvial sediments and the short distance gold moves from its hardrock source.
Once the machine is activated, the finer, gold-bearing material travels down an inclined, vibrating chute, passing over a series of "riffles" in a recovery tray.
A simple one can be constructed using a wooden framework, a hopper, a recovery tray, bellows, lever, and cord.
Before the advent of modern metal screening material, sorting of gravels into smaller particles might have been done by hand.