an eccentric drive as is known the vibratory actuator 42 may be coupled to the trough 12 through at least one link 44 such as for instance a spring assembly together the actuator 42 and the at least one link 44 impart a controlled vibratory conveying force to the trough 12 the vibratory force moves the trough 12 in a vibratory motion that advances material on the trough 12 in a series of gentle throws and catches between the input end 14 and the discharge end 16 an exemplary first separation stage 50 is illustrated generally in fig1 2 the first separation stage 50 includes a deck 52 coupled to the first conveying plateau 20 in a substantially co planar configuration the deck 52 may be for example a solid deck a finger screen deck or any other suitable deck when utilizing a finger screen deck u201c fine u201d particles of a predetermined size may fall through the first conveying plateau 20 for collection for example the deck 52 may include a plurality of apertures sized to allow particles below one half inch in size to pass through the deck 52 to facilitate the collection of fine particles the first separation stage 50 may additionally include a first discharge chute 54 to discharge funnel and collect any material which may fall through the deck 52 additionally located above the first conveying plateau 20 and in this example suspended from the hood 30 above the deck 52 is a flexible flap 56 the flexible flap 56.