igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, dark gray to black color, fine-grained aphanitic texture, and dull luster.
Identified More igneous →
Explore Basalt in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 6 on the Mohs scale, dark gray to black color, fine-grained aphanitic texture, and dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the surface of a planet or moon.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and in the manufacture of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forms famous formations like the Giant's Causeway.
Field identification & locations
Identified by its dark, fine-grained matrix and dense feel; found globally in volcanic regions and oceanic crusts.
