|Name||Coal Creek Serpentinite|
|Geologic age||preCambrian (Proterozoic)|
Metamorphic > Metaigneous > Serpentinitepredominantly medium- to dark-gray, medium- to fine-grained quartz diorite composition. Associated with soapstone and vermiculite
|Comments||Discussed as Coal Creek serpentine mass (Romberg and Barnes, 1949). Bordered by Big Branch Gneiss and Packsaddle Gneiss. (fr. Llano Sheet, Geo. Atlas of TX) Light-green to v. dk. green, varies widely in texture, one large mass in SE Llano region, comprises 2.54 sq.mi. in a mass 3.7 mi long, a potential source for magnesium, silica gel, and byproduct nickel and chromium; sm. bodies in Oxford area south of Llano associ. with soapstone and vermiculite.|
Bureau of Economic Geology, 1981, Llano sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.
Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000.
|Counties||Blanco - Gillespie|