Peridotite
“Mantle material exposed”
Igneous
Peridotite is a dense, dark-green ultramafic igneous rock that makes up most of Earth's upper mantle. Rarely seen at the surface, it appears in ophiolites — slices of oceanic crust and mantle thrust onto continents during tectonic collisions.
Composition
olivine (dominant), pyroxene, garnet, spinel
Where Found
Oman Ophiolite, Troodos (Cyprus), Twin Sisters (Washington, USA), Red Sea Hills (Egypt)
Mohs Hardness
6-7
Fun Fact
When peridotite is exposed at Earth's surface, it naturally absorbs CO₂ from the atmosphere — scientists are studying whether this process could help fight climate change.
Test Your Knowledge
What happens to peridotite's volume and density when it transforms into serpentinite?
Related Specimens
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