igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness 6 on Mohs scale, dark gray to black in color, fine-grained aphanitic texture, dull luster.
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Physical properties
Hardness 6 on Mohs scale, dark gray to black in color, fine-grained aphanitic texture, dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the Earth's surface.
Uses & applications
Used extensively in construction as crushed stone for road bases, concrete aggregate, and in the production of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forming massive volcanic provinces.
Field identification & locations
Identified by its dark color, heavy weight, and fine-grained texture; commonly found in volcanic regions and oceanic crust worldwide.
