Abstract: A sluice assembly for separating heavy particles from slurry is provided. The sluice assembly includes one or more sluice boxes having decks made of plastic having a Shore D hardness between 50-75, a static coefficient of friction less than 0.3 and a kinetic coefficient of friction less than 0.2. In a preferred embodiment, the sluice assembly includes a pair of sluice boxes in which a top sluice box is positioned above the bottom sluice box so that slurry flowing from the downstream end of the first sluice box is received by the upstream end of the bottom sluice box. The bottom deck includes tapered riffles which are arranged to provide “V” shaped diverters for diverting heavier particles for collection. The sluice box upper deck may include laterally extending riffles for collection of heavier particles.