Mica
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Micas are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into fragile elastic plates. This characteristic is described as p
Mica
Sheets of mica
Photomicrographs of a thin section containing phlogopite. In cross-polarized light on the left, plane-polarized light on the right.
Dark mica from eastern Ontario
Schist
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Schist is a medium-grained metamorphic rock generally derived from fine-grained sedimentary rock, like shale. It shows pronounced schistosity. This means that the rock is composed of mineral grains ea
Mica
…and metamorphic rock and is occasionally found as small flakes in sedimentary rock. It is particularly prominent in many granites, pegmatites, and schists, and "books" (large individual crystals) of mica several feet across have been found in some pegmatites. Micas are used in products such as drywalls…
A schist showing characteristic scaly schistose texture caused by platy micas
Microscopic view of garnet-mica-schist in thin section under polarized light with a large garnet crystal (black) in a matrix of quartz and feldspar (white and gray grains) and parallel strands of mica (red, purple and brown).
View of cut garnet-mica-schist
Manhattan schist from southeastern New York State