What term describes light-colored igneous rocks that are rich in feldspar and quartz?

The term that describes light-colored igneous rocks rich in feldspar and quartz is "felsic." Felsic rocks are characterized by their high silica content and lighter color due to the abundance of light-colored minerals, primarily quartz and feldspar. This composition is typically found in rocks such as granite and rhyolite, which are formed from the cooling and solidification of magma. The presence of these minerals gives felsic rocks their distinctive appearance and influences their physical properties, making them less dense than mafic rocks, which are higher in magnesium and iron.

In contrast, the other terms do not accurately describe this type of rock. "Foliated" refers to a specific texture found in some metamorphic rocks, indicating a layered or banded appearance, which is unrelated to the composition of igneous rocks. "Mafic" describes igneous rocks that are darker and richer in magnesium and iron, such as basalt and gabbro, contrasting with the light coloration of felsic rocks. Lastly, "metamorphic" pertains to rocks that have undergone significant changes due to heat and pressure, excluding all igneous rocks from consideration. Thus, "felsic" is the precise term for the light-colored igneous rocks rich