Porphyroblastic mica schist, characterized by 1- to 2-mm garnet porphyroblasts in an anastomosing, greenish-black biotite-rich, schistose matrix. Most exposures show complex microstructures suggestive of polyphase deformation and superimposed shearing. In Appomattox and Campbell counties, and locally elsewhere,this unit includes quartzose muscovite schist along the western and eastern margins of the outcrop belt (presumed base of the stratigraphic section); locally the unit contains thin interbeds of calcareous mica schist and marble. Mineralogy: biotite + garnet + muscovite + quartz + plagioclase + magnetite ± kyanite ± calcite. Geophysical signature: characterized by elongate positive magnetic and radiometric anomalies. This unit was mapped in strike-belts southwest of, and not physicaly connected to the type section at Arvonia.
Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000.
Virginia Division of Mineral Resources, 2003, Digital Representation of the 1993 Geologic Map of Virginia, Publication 174, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, scale 1:500,000.