Over 4 billion years ago.
Such rock is extrusive igneous rock.
Igneous rock. Extrusive igneous rock forms at or near the surface, intrusive igneous rock forms below the surface.
Intrusive igneous rock
Intrusive igneous rock (plutonic rock).
a Obsidion rock
extrusive igneous rock.
Igneous rock that forms below the Earth's surface is intrusive.
Extrusive (volcanic) and exposed plutonic igneous rock.
Intrusive igneous rock
Intrusive igneous rock
extrusive igneous rock
Extrusive igneous rock.