Search U.S. government technical reports digitized or harvested by TRAIL.
Placer mining in the western United States :part 1. general information, hand-shoveling, and ground-sluicing
Placer mining in the western United States :part II. Hydraulicking, treatment of placer concentrates, and marketing of gold
Placer mining in the western United States :part III. Dredging and other forms of mechanical handling of gravel, and drift mining
Placer-mining methods of E.T. Fisher Co., Atlantic City, Wyo.
Placer operations of Humphreys Gold Corporation, Clear Creek, Colo.