Prospecting Equipment for sale Mini Highbanker, built this myself out of heavy duty aluminum. (1/8") thick. Sluice Box is 36" x 12", 1/16" 5052 aluminum by West Yuba Mining. Ribbed matting full length of the sluice box. Miner's Moss and Steel Hydraulic Riffles. Splash plate, perforated Steel plate at the top of the sluice box.