Abstract: A machine for wet-processing ore to recover precious metal values such as gold. The machine includes a rotating, inner, perforate, hollow, ore-receiving drum and also a vibrating cradle for receiving water, sands, and other relatively fine material as is discharged through the perforations of such drum. The drum is provided with an inner spiral protuberance for advancing materials from the receiving to the discharge end thereof. Additionally, impact means as are disposed between turns of such spiral are employed to advance rapidly, larger materials such as rocks and coarse gravel through the drum. The cradle is provided with an auger for discharging materials from the cradle; said cradle is so designed and positioned as to concentrate finer materials such as gold-containing black sand, proximate a lowered, reservoir-end thereof for discharge.