Bowen's Reaction Series
The Sequence of Mineral Crystallization
1200°C
700°C
Discontinuous Series
Olivine
(Mg,Fe)₂SiO₄
Pyroxene
(Mg,Fe)SiO₃
Amphibole
NaCa₂(Mg,Fe)₅Si₈O₂₂
Biotite Mica
K(Mg,Fe)₃AlSi₃O₁₀(OH)₂
Continuous Series
Ca-rich Plagioclase
Anorthite (CaAl₂Si₂O₈)
Sodium (Na) replaces Calcium (Ca) continuously in the crystal lattice.
Na-rich Plagioclase
Albite (NaAlSi₃O₈)
Potassium Feldspar
KAlSi₃O₈ (Orthoclase)
Muscovite Mica
KAl₂(AlSi₃O₁₀)(OH)₂
Quartz
SiO₂
Ultramafic
Peridotite
Mafic
Basalt / Gabbro
Intermediate
Andesite / Diorite
Felsic
Rhyolite / Granite
The "Hot" End
Minerals at the top (Olivine, Ca-Plagioclase) are Mafic. They are rich in Magnesium and Iron, dense, and dark in color. They are unstable at Earth's surface and weather quickly.
The "Cool" End
Minerals at the bottom (Quartz, K-Feldspar) are Felsic. They are rich in Silica, lighter in color, and less dense. Quartz is the most chemically stable mineral at surface pressures.