Coal Creek Serpentinite

Coal Creek Serpentinite
State Texas
Name Coal Creek Serpentinite
Geologic age preCambrian (Proterozoic)
Lithologic constituents
Major
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.
References

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.

NGMDB product
Counties Blanco - Gillespie