Search U.S. government technical reports digitized or harvested by TRAIL.
Blast-hole diamond drilling in California mines
Method and cost of driving the Rock Creek Tunnel, Hecla Mining Co., Shoshone County, Idaho
Phosphate rock mining in southeastern Idaho
Investigation of tungsten occurrences in Darwin District, Inyo County, Calif.
Mining methods and costs at the Highland Surprise Mine, Shoshone County, Idaho