Abstract

Southwestern Wyoming (defined here as east of the Overthrust Belt and west of the Continental Divide) contains significant nonfuel mineral resources. Chief among these is the trona deposit in the Green River Basin. This resource is covered by other articles in this guidebook, and will not be discussed here in detail. Other industrial minerals currently being produced in southwestern Wyoming include construction aggregate (river rock and crushed rock) and recovered sulfur. Wyoming is second among states in the amount of sulfur recovered from oil and gas refining. Some of this sulfur is combined with phosphate mined in Utah to produce soil conditioners at a plant southeast of Rock Springs.

Industrial minerals produced from southwestern Wyoming in the past include chemical grade limestone, mineral pigments, silica sand for glass manufacture, sodium sulfate, and steatite. There are small occurrences of alunite, titanium-bearing black sands, and refractory clay, but these have not been produced.

Industrial minerals in southwestern Wyoming with potential for future production include railroad ballast and decorative aggregate from igneous rocks in the Leucite Hills, dimensional sandstone from the Rock Springs uplift and near Rawlins, and zeolites. Significant resources of clinoptilolite, a zeolite mineral, exist in the Washakie Formation around the Washakie Basin, and economically minable deposits are found on the north and west margins of the basin.