Granodiorite
“The most common plutonic rock on Earth”
Granodiorite is a coarse-grained intrusive rock that sits between granite and diorite in composition, with more plagioclase than alkali feldspar. It's arguably the most abundant plutonic rock in Earth's continental crust, forming the cores of mountain belts and vast batholiths worldwide.
plagioclase feldspar, quartz, alkali feldspar, biotite, hornblende
Sierra Nevada (California, USA), Andes, Coast Plutonic Complex (British Columbia), Scotland, Finland
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The Rosetta Stone — one of the most famous archaeological artifacts in history — is actually carved from granodiorite, not granite or basalt as was long believed.
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Why was the Rosetta Stone long misidentified as granite or basalt?
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