Igneous rock (derived from the Latin word ignis meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

Igneous rocks are Earth’s original rocks. They form when magma (molten rock within the Earth) or lava (at the surface) cools to stone. The composition of the rock that melts and where that melt later ...

From the lab bench to the field, learning to identify rocks is about more than memorizing names—it’s about reading the story each stone tells. By observing texture, composition, and formation clues, ...