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• Alkaline rocks
• Felsic rocks
• Description of igneous rocks

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ULTRAMAFIC ROCKS

These rocks contain less than 45% silica. The most characteristic minerals are olivines, pyroxenes, hornblende. These rocks are dark, sometimes green (olivine) because of the mafic minerals in their composition.

Dunite

Dunite consist almost entirely of olivine, often accompanied by accessory chrome spinel.

PPLXPL

Describing:Texture: holocrystalline, phaneritic

Minerals: olivine

Peridotite

Peridotite is an olivine-rich, coarse-grained rock. This rocks are subjected to serpentinisation. Peridotite do not have volcanic equivalent.

PPLXPL

Describing:Texture: holocrystalline, phaneritic

Minerals: olivine, pyroxene

Pyroxenite and hornblendite

Pyroxenite and hornblendite mostly consist of pyroxenes and hornblende, respectively there are some possible accessory minerals like olivine, feldspar, nepheline.