Hydraulic Riffles ? Gold Dredging Forum
23/04/2011· In particular, if using a production dredge to dredge a widely dispersed deposit of fine gold from the overburden, then its well worth while going to the trouble of ripping out conventional riffles and replacing them with hydraulic riffles. Regards, Rob Last Edit: Apr 13, 2010 at 1:41am by RKC. aucn.