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Granite
Rock type:
Age:
251 millions years
Submitted 4 years 7 months ago by rock.
Russia, Altai, rock "Four brothers". Belokurikhinsky granite massif. Porphyry biotite granites. Medium grained. Porphyry phenocrysts - microcline. Consist: microcline - 35-65%, plagioclase - 10-30%, quartz 20-30% biotite - 4-7%. Accessory: magnetite, zircon, apatite, muscovite. Upper Permian - Low Triassic.
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