&start=Press Start to begin
&part1=Volcanoes erupt causing magma to spill out onto the Earth's surface.
&part2=Eventually the magma cools, forming extrusive igneous rock.
&part3=Magma cools slowly, and as a result large, interlocking crystals form.
&end=Press Start to play the animation again.

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&info.info1=Press the Start button to watch the animation. At any point you can press the Pause button. Press the Menu button to go back to the main menu.