Simplified classification of igneous rocks
| Chemical class: | Ultramafic | Mafic | Intermediate | Felsic |
| Color | dark | dark | medium | light |
| SiO2 % | <45 | 45-53 | 53-65 | >65 |
Grain size: |
(komatiite) | basalt | andesite | rhyolite |
Grain size: |
peridotite | gabbro | diorite | granite |
| mafic minerals | olivine, pyroxene |
(olivine), pyroxene, |
pyroxene, hornblende, |
hornblende, biotite |
| felsic minerals | Ca-plagioclase | Ca- to Na- plagioclase, (quartz) |
Na- plagioclase, K-feldspar, muscovite, quartz |