Igneous rocks main content.

Exhibition Text

Igneous rocks solidify from molten rock (called magma within the Earth and lava on the surface). They are identified by mineral content and texture — the size and shape of their mineral grains.

Texture is controlled by the rate of cooling: magma that cools slowly deep in the Earth forms rock with large crystals, and lava that cools quickly on the surface forms fine-grained rock.

For Educators

Topic: Earth Science