Quartzite

Light-gray to pinkish-gray, magnetite-muscovite-plagioclase quartzite at Devils Den. Grades into structurally overlying biotite-muscovite feldspathic schist and garnet-bearing feldspathic gneiss that contains pegmatite. Mount Holly Complex paragneiss. Rocks of the Green Mountain and Lincoln Mountain massifs and eastern domes. Unit is part of the Problematic rocks at Devils Den in Weston and Danby areas: Near Devils Den and Moses Pond includes albitic biotite-muscovite schist, chloritoid-chlorite-muscovite (┬▒garnet) schist, dolomite marble and minor quartzite which resemble rocks of the Tyson Formation, and retrograde varieties of the paragneisses of the Mount Holly Complex. Because these rocks are structurally compatible with Grenvillian or older folds in the Mount Holly Complex and are transitional into rocks of the Mount Holly Complex, a Mesoproterozoic age is favored. Nevertheless the resemblance to rocks of the Tyson Formation is striking.
State Vermont
Name Quartzite
Geologic age Middle to Early Mesoproterozoic
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > QuartziteLight-gray to pinkish-gray, magnetite-muscovite-plagioclase quartzite at Devils Den.
Minor
Metamorphic > Metasedimentary > ParagneissGarnet-bearing feldspathic gneiss that contains pegmatite.
Metamorphic > Schist > Mica-schistBiotite-muscovite feldspathic schist.
Incidental
Igneous > Plutonic > Granitic > Leucocratic-granitic > PegmatiteGarnet-bearing feldspathic gneiss that contains pegmatite.
References
NGMDB product
Counties Rutland