View your list of saved words. (You can log in using Facebook.)
In geology, any igneous rock dominated by the silicates pyroxene, amphibole, olivine, and mica. These minerals are high in magnesium and ferrous iron, and their presence gives mafic rock its characteristic dark colour. It is usually contrasted with felsic rock. Common mafic rocks include basalt and gabbro.
This entry comes from Encyclopædia Britannica Concise. For the full entry on mafic rock, visit Britannica.com.
Seen & Heard
What made you look up mafic rock? Please tell us what you were reading, watching or discussing that led you here.