Igneous rocks primarily contain minerals that crystallize from molten magma or lava. The most common minerals found in these rocks include:
- Feldspar: This group of minerals makes up a significant portion of igneous rocks. They can be divided into two categories: plagioclase and potassium feldspar. These minerals are essential for defining the composition of many igneous rocks.
- Quartz: Often found in more evolved or silicic igneous rocks, quartz is a key component due to its resistance to weathering and its abundance in the Earth’s crust.
- Mica: This group includes biotite and muscovite, commonly found in various igneous rocks, adding to their texture and appearance.
- Pyrroxene: A dark, mineral often found in basalt and gabbro, pyroxene minerals play a crucial role in the composition of mafic rocks.
- Amphibole: Similar to pyroxene but containing water in its structure, amphibole is commonly present in intermediate to felsic igneous rocks.
- Olivine: Typically found in ultramafic rocks like peridotite and basalt, olivine is a key mineral in the formation of the Earth’s mantle.
These minerals contribute to the overall characteristics and classification of igneous rocks. The specific minerals present can vary greatly depending on the chemical composition of the original magma and the environment in which the rock formed.