Igneous rocks form when magma cools underground or erupts at the surface as lava. The magma rises into the Earth’s crust, where it can get trapped underground or erupt from volcanoes as molten lava.

Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the gasses shatters the magma and propels it into ...

Like other igneous rocks, the glossy glass originates from molten rock that has been spewed out from the bowels of the Earth via volcanoes. Before we get into the snowflakes, obsidian is formed ...

What preserved this prehistoric village, what formed a perfect impression of ... a truly astonishing array of curios carved from volcanic rock (Buddha, the Pietà, frogs, owls, the Three Graces ...