igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black in color, aphanitic texture, and submetallic to 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, typically dark gray to black in color, aphanitic texture, and submetallic to dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in magnesium and iron exposed at or very near the Earth's surface.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and manufacturing of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and is also found abundantly on the Moon and Mars.
Field identification & locations
Easily identified by its dark, fine-grained appearance and heavy density. Found globally in volcanic provinces and oceanic islands.
