Our Ancestors Crafted Hand Axes From Cold Lava, Tool Factory Unearthed in Ethiopia Depicts Their Advancement Human ancestry ...

This molten earth origin is what classes rainbow obsidian as an igneous rock. Lava destined to become obsidian cools rapidly once on the surface and, thanks to its viscous nature, is also below ...

Extrusive igneous rocks are formed by magma that has erupted onto the surface as lava and then cooled quickly. Obsidian is an example of an extrusive igneous rock. Obsidian has crystals which are ...

Volcanic rock is formed when lava or magma cools down and becomes a solid. We call this type of rock igneous rock. Here are three different types of igneous rock from the Museum’s collection.