Abstract: A material separator includes a housing defining a settling chamber, a communicating drain chamber and a discharge member. A horizontal screw conveyor extends through the settling chamber and drain chamber to the discharge chamber. Material to be separated is introduced into the housing at the top of the settling chamber and water is introduced into the bottom of the settling chamber at a flow rate sufficient to partially immerse the conveyor. The heavier material components sink to the bottom of the settling chamber while the desired lighter components float and are advanced by the conveyor and water flow into the drain chamber. In the drain chamber, the horizontal screw conveyor is tapered inwardly as the screw conveyor traverses the discharge chamber and a tapered screen is positioned around the tapered screw conveyor to rotate therewith.