igneous
Basalt
Mafic 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 subconchoidal fracture.
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 subconchoidal fracture.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava flows exposed at or near the Earth's surface.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and in the production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crustal portions underlying the ocean basins and also forms major volcanic landforms on terrestrial planets.
Field identification & locations
Identified in the field by its dark color, fine-grained matrix, and frequent vesicular texture from trapped gas bubbles; common globally in volcanic regions.
