Serpentinite
“The snake-skinned rock”
Metamorphic
Serpentinite is a metamorphic rock formed when ultramafic mantle rocks like peridotite are hydrated and altered by water at tectonic boundaries. Its waxy, green surface often resembles snakeskin, and it marks the locations of ancient subduction zones.
Composition
serpentine group minerals (antigorite, chrysotile, lizardite)
Where Found
California Coast Ranges (USA — it's the state rock), Cyprus, New Caledonia, Oman
Mohs Hardness
3-5
Fun Fact
Serpentinite is the official state rock of California and is commonly found along the San Andreas Fault system.
Test Your Knowledge
Why are soils derived from serpentinite often barren and hostile to most plant life?
Related Specimens
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