pumice: Quick Facts

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Mount St. Helens eruption.

Study how magma erupts as lava and turns into pumice or hardens to form a shield volcano

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Topics

volcanic glass extrusive rock basalt perlite trachyte obsidian rhyolite phonolite andesite diabase pitchstone spilite

Basalt sample returned by Apollo 15, from near a long sinous lunar valley called Hadley Rille. Measured at 3.3 years old.

(Bed) Rocks and (Flint) Stones