Wanna have some fun? Gather some geologists around a sample that might be phyllite or might be schist and watch them go.

Phyllite is a protolith of schist.

Rock group	Metamorphic
Metamorphism type	Regional
Metamorphic rock class	Pelitic Marl
Protolith	Slate

Phyllite in Hand Sample

Archean-aged phyllite from Ontario
Crossbedding preserved in phyllite
Phyllite ft. pyrite

Phyllite in Thin Section

Chlorite-rich phyllite, plane polars
Chlorite-rich phyllite, crossed polars

Phyllite, Plane Polars

Phyllite in plane polarized light. Magnification: 40x Click here to see phyllite rotating in crossed polars: https://youtu.be/gf44XfVCMhk Click here to explo…

Phyllite, Crossed Polars

Phyllite in cross polarized light. Magnification: 40x Click here to see phyllite rotating in plane polars: https://youtu.be/ifi9SAJGbfc Click here to explore…