Mafic vs. Felsic

Maficadjective

(geology) Describing rocks, such as silicate minerals, magmas, and volcanic and intrusive igneous rocks, which contain relatively high concentrations of magnesium and iron.

Maficnoun

A rock with such properties.

Mafic

A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite.

Felsicadjective

(mineralogy) Enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium.

Felsicnoun

A rock with such properties.

Felsic

In geology, felsic is an adjective describing igneous rocks that are relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are relatively richer in magnesium and iron.