Peridotite

A peridotite is a hard and rough igneous rock, made up mostly of the minerals olivine and pyroxene. It is named for Peridot.

Peridotite Media

Classification diagram for peridotite and pyroxenite, based on proportions of olivine and pyroxene. The pale green area encompasses the most common compositions of peridotite in the upper part of the Earth's mantle (partly adapted from Bodinier and Godard (2004)).
Typical peridotite sample (dunite, left) and large olivine crystal (right)
Olivine in a peridotite weathering to iddingsite within a mantle xenolith
Serpentinized and carbonated peridotite
Alpine peridotite from the Ivrea zone in the Alps of Italy (dunite from Finero)
Peridotite xenoliths in phonotephrite, from Arizona

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