Mica Schist

Physical Properties

Hardness: 3.5-4; Color: Silvery-grey to dark brown; Luster: Pearly to sub-metallic; Structure: Foliated with visible mica flakes (schistosity); Cleavage: Perfect basal on mica flakes; Specific gravity: 2.7-2.8

Formation & Geological History

Formed through medium-grade regional metamorphism of shale or mudstone. Subjected to high heat and pressure which causes mica minerals to align and grow.

Uses & Applications

Commonly used as building stone, flagstone, decorative garden stone, and occasionally as a source of scrap mica for specialized industrial insulation.

Geological Facts

The word 'schist' is derived from the Greek word 'schizein', meaning 'to split', referring to the ease with which the rock can be split along the planes of its micaceous minerals.

Field Identification & Locations

Identify by its 'shimmery' or glittery appearance when moved in the light and its tendency to flake or split into thin layers. Found in mountain belts and shield areas.

Identified on: 4/18/2026

Mode: Standard