Texas' Hudspeth County talc mining, begun in 1952 when Southwestern Talc Corp. carried out pioneer exploratory operations, has expanded during the last five years and can today claim six active operations. These Include (1) Southwestern Talc Corp., Llano, Texas, (2) West Texas Talc Corp.
The rim rock of the Vieja Rim, the quartz pantellerite of Lord, is named the Bracks Rhyolite.
The Colorado River Industrial Development Association area consists of ten counties [Bastrop, Blanco, Burnet, Colorado, Fayette, Llano, Matagorda, San Saba, Travis, and Wharton counties] in the lower watershed of Colorado River in Texas.
The eastern margin of the High Plains in central western Texas affords particularly good opportunity for study of late Cenozoic geology. The topography of the area is dominated by the southernmost segment of the late Tertiary mantle of fluvial sediments, isolated from the central and northern High Plains by the valley of the Canadian River.