The peridotite “family” contains a number of different intrusive igneous rocks. These include lherzolite, harzburgite, dunite, wehrlite, and kimberlite (see photos). Most of them have an obvious green color, attributed to their olivine content.
- Lherzolite: a peridotite composed primarily of olivine with significant amounts of orthopyroxene and clinopyroxene. Some researchers believe that much of Earth’s mantle is composed of lherzolite.
- Harzburgite: a peridotite composed primarily of olivine and orthopyroxene with small amounts of spinel and garnet.
- Dunite: a peridotite that is composed mainly of olivine and may contain significant amounts of chromite, pyroxene, and spinel.
- Wehrlite: a peridotite that is composed mainly of orthopyroxene and clinopyroxene, with olivine and hornblende.
- Kimberlite: a peridotite that is composed of at least 35% olivine with significant amounts of other minerals that might include phlogopite, pyroxenes, carbonates, serpentine, diopside, monticellite, and garnet. Kimberlite sometimes contains diamonds.
