Garnet Granulite
“From the deepest continental crust”
Garnet granulite is a high-grade metamorphic rock characterized by garnet and pyroxene in a granular, non-foliated texture. It forms at the base of continental crust under extreme temperatures (700-900°C) and pressures, representing some of the deepest-formed rocks that return to the surface.
garnet (pyrope-almandine), clinopyroxene, orthopyroxene, plagioclase, quartz, rutile
Ivrea Zone (Italy), Limpopo Belt (Zimbabwe/South Africa), Eastern Ghats (India), Adirondacks (USA), Mawson Coast (Antarctica)
6-7
The Ivrea Zone in the Italian Alps exposes a complete cross-section of the lower continental crust, including garnet granulites from depths of 25-30 km — it's the closest thing to a drill core through the deep crust that nature provides.
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Related Specimens
Eclogite (Garnet-Omphacite)
“The densest rock at Earth's surface”
Phengite Schist
“High-pressure mica from subduction zones”
Amphibolite (Garnet-bearing)
“Dark amphibole rock with garnet treasures”
Cordierite-Anthophyllite Rock
“Metamorphosed from chemically exotic protoliths”
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