Description obsidian (/əbˈsɪdi.ən) is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth //
an igneous rock //
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Description obsidian (/əbˈsɪdi.ən) is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth //
an igneous rock //
2000x3000px //