metamorphic
Mica Schist
Metamorphic rock dominated by mica minerals
Hardness of 3-4 on the Mohs scale, silvery-gray to brown color, pearly or metallic luster due to abundant mica flakes, foliated crystal structure with prominent schistosity, excellent cleavage along planes, specific gravity around 2.7-2.9
Identified More metamorphic →
Explore Mica Schist in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 3-4 on the Mohs scale, silvery-gray to brown color, pearly or metallic luster due to abundant mica flakes, foliated crystal structure with prominent schistosity, excellent cleavage along planes, specific gravity around 2.7-2.9
Formation & geological history
Formed through regional metamorphism of argillaceous rocks like pelitic clay and shale, typically occurring during mountain-building events (orogenies) at elevated temperatures and pressures.
Uses & applications
Used primarily in decorative garden stone, as a source of scrap mica, sometimes in construction fill, and popular in geological education and specimen collecting.
Geological facts
The prominent shimmering appearance is caused by the alignment of reflective muscovite or biotite mica crystals perpendicular to the direction of maximum principal stress.
Field identification & locations
Easily identified in the field by its distinct foliation and sparkly, sheet-like mica minerals covering the cleavage surfaces. Found globally in ancient mountain belts and shield areas.
More like this
