Rusty mica schist and gneiss

(Equivalent in part to Washington Gneiss of Massachusetts) - Dark-gray, rusty-weathering, well-foliated and well- to poorly layered schist and gneiss composed of quartz, plagioclase, biotite, muscovite, sillimanite, and locally garnet; some layers of feldspathic quartzite and garnetiferous amphibolite.
State Connecticut
Name Rusty mica schist and gneiss
Geologic age Proterozoic Y; may contain some older rocks
Lithologic constituents
Major
Metamorphic > GneissDark-gray, rusty-weathering, well-foliated and well- to poorly layered schist and gneiss composed of quartz, plagioclase, biotite, muscovite, sillimanite, and locally garnet.
Minor
Metamorphic > SchistDark-gray, rusty-weathering, well-foliated and well- to poorly layered schist and gneiss composed of quartz, plagioclase, biotite, muscovite, sillimanite, and locally garnet.
Incidental
Metamorphic > Metasedimentary > Metaclastic > Quartzitesome layers of feldspathic quartzite
Metamorphic > Amphibolitesome layers of garnetiferous amphibolite
Comments Part of Western Uplands; Proto-North American (Continental) Terrane - Proterozoic Massifs - ""Grenville""
References

Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.

NGMDB product
Counties Fairfield - Hartford - Litchfield