Question

Phyllite and schist are both metamorphic rocks. When you examine the rock samples, you will be able to see that schist has visible mineral crystals, but phyllite does not. Can you tell which rock has undergone higher temperature and pressure conditions (has a higher metamorphic grade)? If so, which one?

1) Phyllite
2) Schist
3) Both have the same metamorphic grade
4)You can't tell just by looking at the rocks

Answer 1

1)Phyllite

Step-by-step explanation:

The rock which has undergone more temperature and pressure conditions is Phyllite which is also known as Gneiss.

Schist and Phyllite are produced by the process of medium to high grade metamorphism. But in some cases Phyllite is produced by high grade metamorphism when compared to schist. The Low-grade metamorphic rocks always tend to be fine-grained. High-grade metamorphic rocks are often tend to be coarse-grained.

Phyllite is a high grade metamorphic rock,which means it has been subjected to higher temperatures and pressures than schist. Phyllite is formed by the metamorphosis of granite, or the sedimentary rock. Gneiss/Phyllite displays distinct defoliation, representing the alternating layers composed of different mineral forms.