Basanite
“Dark lava with a hint of olivine”
Basanite is a dark, fine-grained volcanic rock similar to basalt but containing nepheline or leucite in addition to olivine and pyroxene. It erupts from alkali-rich magmas in continental rift zones and oceanic islands, often carrying fragments of mantle rock to the surface as xenoliths.
plagioclase, olivine, augite, nepheline or leucite, magnetite
Eifel (Germany), Canary Islands, East African Rift, Auvergne (France), eastern Australia
5.5-6
Basanite lavas from the Eifel region of Germany frequently bring up chunks of the mantle called peridotite xenoliths — they're like geological care packages from 60+ km below the surface.
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