Mica

These specimens are mica-rich metamorphic rocks displaying well-developed foliation and cleavage, characteristic of mica minerals. The platy, sheet-like crystals split easily along basal planes, producing the reflective, layered surfaces visible in both pieces.

Mica forms during regional metamorphism, where clay-rich sedimentary rocks are subjected to elevated temperature and pressure, causing minerals to recrystallise and align perpendicular to stress. The result is a rock with strong planar fabric and a silky to pearly lustre.

The left-hand specimen shows coarser, more distinct mica plates, while the right-hand specimen preserves a thicker, layered mass with mica concentrated along foliation planes. Together, they make an excellent comparative set for illustrating mineral cleavage, metamorphic texture, and foliation development.

100 x 80 x 25mm

104g