Pegmatites,which often occur in dikes,are unusual among shallow intrusive rocks in that they
A) possess porphyritic texture.
B) possess exceptionally coarse grains.
C) are mineralogically identical to basalt.
D) are glassy,cooling so rapidly that crystals do not have time to form.

Question

Quizplus · Accepted Answer

Pegmatites possess exceptionally coarse grains, often containing minerals that are rare or absent in other rocks. This makes them unusual among shallow intrusive rocks.

Pegmatites,which Often Occur in Dikes,are Unusual Among Shallow Intrusive Rocks