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A fine-crystalline rock consisting of plagioclase and pyroxene.Lava is molten rock expelled by a volcano during an eruption.


When first expelled from a volcanic vent, it is a liquid at temperatures from 700 °C to 1,200 °C. Although lava is quite viscous, with about 100,000 times the viscosity of water, it can flow great distances before cooling and solidifying, because of its thixotropic and shear thinning properties.


A lava flow is a (moving) outpouring of lava, which is created during a non-explosive effusive eruption. When it has stopped moving, lava solidifies to form igneous rock. The term lava flow is commonly shortened to lava.



Lava with pipe-amygdales

A fine-crystalline rock consisting of plagioclase and pyroxene.


Ropy lava

This rock is fine-crystalline and consists of plagioclase and pyroxene.