What is the name of the process in which minerals crystallize from cooling magma?

Crystallization is the process in which minerals crystallize from cooling magma.

As magma loses heat, atoms and ions arrange themselves into ordered crystal structures. Different minerals form at different temperatures and under different chemical conditions. In many magmas, high-temperature minerals such as olivine and pyroxene crystallize before lower-temperature minerals such as quartz.

Underground magma cools slowly, allowing larger crystals to grow and producing intrusive rocks such as granite and gabbro. Lava cools much faster at the surface, usually producing fine-grained rocks such as basalt or, if cooling is exceptionally rapid, volcanic glass such as obsidian.

Mineral crystallization can change the composition of the remaining liquid magma. This principle is central to Bowen’s reaction series, which describes common crystallization sequences in silicate magmas. Crystallization is different from lithification, which turns loose sediment into sedimentary rock, and from metamorphism, which alters existing rock in the solid state.