Geological Survey Bulletin, Issue 1042

andesitic Argillite banded belt breccia Calcite Operators calcite veins Cambrian Clyde Park Coastal Plain consists contains cubic yard diorite diorite porphyry dolomite east Elkhorn Mountains Elkhorn Mountains volcanics faults feet thick fine-grained finely crystalline Flathead quartzite folding fraction geologic grained gravel gray Greyson shale heavy minerals hornblende Hossfeldt Hills inches Indian Creek Killorn Klepper Limestone Hills Livingston formation Lone Mountain map area Meagher limestone Mertie Metals Reserve Company miles west mined Miocene Missouri River monazite monazite content monazite per cubic Montana Oligocene Oligocene sedimentary tuff optical calcite outcrops percent Pilgrim dolomite placer plagioclase Pleistocene Pliocene porphyry pounds of optical probably quartz quartzite Ruppel samples sand sandstone sediments shaft shale siltstone southwest Spokane shale stope surface Sweet Grass County thin beds Three Forks Townsend Valley tuff Tuscaloosa Tuscaloosa formation U. S. Route upper vugs Wade property wall rock weakly magnetic west of Lone zone