metamorphic

Likely biotite-rich schist

Mica schist, chiefly quartz and mica (commonly biotite; possible muscovite)

AI-generated identification · may be incorrect

Gray, coarse-grained, sparkly specimen with mica flakes and possible foliation; mica has Mohs hardness 2–3 and perfect basal cleavage, while quartz is 7. The photo alone does not confirm mineral proportions or exact identification.

Identified October 6, 2026More metamorphic →

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Physical properties

Formation & geological history

Formed when clay-rich sedimentary rock or similar material was buried and metamorphosed under heat and pressure; age depends on its source region.

Uses & applications

Schist is used as decorative building stone, landscaping material, and a teaching or collecting specimen; flaky mica has limited industrial uses.

Geological facts

The glitter comes from reflective mica grains. Schistosity develops as platy minerals align during metamorphism.

Field identification & locations

Look for visible aligned mica flakes and a tendency to split along wavy, glittering layers; this small fragment’s exact locality and identification cannot be determined from the image.