Biotite Gneiss and Schist (VAbgs;0)

State	Virginia
Name	Biotite Gneiss and Schist
Geologic age	Proterozoic
Original map label	bgs
Comments	Central Piedmont From expanded explanation (ref. VA002): Biotite gneiss and schist:. Dark-gray, medium grained, foliated and broadly-layered. Mineralogy: biotite + plagioclase + potassium feldspar + quartz + muscovite; accessory minerals include titanite, epidote, and opaque minerals.
Primary rock type	gneiss
Secondary rock type	schist
Other rock types
Lithologic constituents	Major Metamorphic > Gneiss > Biotite-gneissBiotite gneiss Metamorphic > Schist
Map references	Digital Representation of the 1993 Geologic Map of Virginia", 2003, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, viewing software not included. This is a digital version of "Geologic Map of Virginia" published in 1993. Available from: https://www.dmme.virginia.gov/commerce/ [https://www.dmme.virginia.gov/commerce/]
Unit references	Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000 Digital Representation of the 1993 Geologic Map of Virginia - expanded explanation: 2003, Commonwealth of Virginia, Department of Mines, Minerals, and Energy, Divsion of Mineral Resources, Publication 147, 85 pp Digital Representation of the 1993 Geologic Map of Virginia", 2003, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, viewing software not included. This is a digital version of "Geologic Map of Virginia" published in 1993. Available from: https://www.dmme.virginia.gov/commerce/ [https://www.dmme.virginia.gov/commerce/]
Geographic coverage	Lunenburg - Prince Edward