Rock Identifier
Basalt (Basalt) — Igneous
Igneous

Basalt

Basalt

Dark-colored, fine-grained, igneous rock. Hardness of 5-6 on the Mohs scale. Composed mainly of plagioclase and pyroxene minerals.

Identified More igneous

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Dark-colored, fine-grained, igneous rock. Hardness of 5-6 on the Mohs scale. Composed mainly of plagioclase and pyroxene minerals.

Formation & geological history

Forms from the rapid cooling of basaltic lava exposed at or very near the surface of a planet or moon. Underlies more of Earth's surface than any other rock type.

Uses & applications

Used in construction, as aggregate or crushed stone. Also used for cobblestones and statues.

Geological facts

Basalt is the most common rock type in the Earth's crust. Most ocean floor is made of basalt.

Field identification & locations

Identified by its dark color and fine-grained texture. Found worldwide, particularly in volcanic islands like Hawaii or mid-ocean ridges.