metamorphic

Likely mica-rich metamorphic rock (schist/phyllite)

Muscovite–quartz–feldspar schist, possibly chlorite schist

AI-generated identification · may be incorrect

Gray-green, fine- to medium-grained, strongly foliated and sparkly from platy mica; uneven fracture with possible cleavage along foliation. Typical hardness is ~2–3 for mica surfaces and ~6–7 for quartz grains; luster ranges from silky to pearly.

Identified September 20, 2026More metamorphic →

Explore Likely mica-rich metamorphic rock (schist/phyllite) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed when shale or volcanic sediment was buried, heated, and compressed, aligning mica minerals into layers. Such rocks commonly formed during Paleozoic–Variscan mountain building, relevant to the Bohemian Massif near 48.5°N, 13.2°E.

Uses & applications

Used locally as building or landscaping stone and occasionally as decorative slab material; generally low gem value.

Geological facts

The green coloration may reflect chlorite or epidote, while silver flashes indicate muscovite. The photograph supports a rock-level identification, but mineral percentages cannot be confirmed without a hand lens or thin section.

Field identification & locations

In the field, test for thin layers that split, visible mica sparkle, and a lack of vesicles. The region is geologically plausible for metamorphic rocks of the Bohemian Massif, though exact identification requires hardness, streak, and acid tests.