| Rock class: | Regional Metamorphic Rock |
| Composition: | Feldspar, mica, and others. |
| Color: | Light, dark, banded |
| Fracture: | Slabs, chunks |
| Grain: | Medium, Coarse |
| Environment: | Often form from fine-grained sedimentary rocks and schists. |
| Comments: | Medium to high grade metamorphism. |