Mafic
Mafic describes rock or minerals rich in magnesium and iron, such as basalt, olivine and pyroxene.
Mafic is a word made from magnesium and ferrum, the Latin for iron. It describes minerals and rocks rich in these two elements, usually dark in colour. Olivine and pyroxene are mafic minerals, and basalt and gabbro are mafic rocks. The opposite term, felsic, describes pale rocks rich in feldspar and silica, such as granite.
Most meteorites are mafic or even more magnesium-rich, called ultramafic. Chondrites are dominated by olivine and pyroxene, diogenites are nearly all pyroxene and chassignites are mostly olivine. Eucrites and shergottites are mafic basalts, much like the volcanic rock of Iceland or Hawaii.
Felsic rocks are almost absent from meteorites, because making them usually requires repeated melting and the action of water, as happened in Earth's continents. A few rare meteorites and clasts with granite-like or andesite-like chemistry have been found, and they are studied closely for what they reveal about early crust formation.
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