igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness 6 on the Mohs scale; typically dark grey to black in color; aphanitic to porphyritic texture with a dull luster.
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Physical properties
Hardness 6 on the Mohs scale; typically dark grey to black in color; aphanitic to porphyritic texture with a 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
Widely used in construction as crushed stone for road bases, concrete aggregate, and in the manufacturing of rock wool insulation.
Geological facts
Basalt is the most common rock type on Earth's crust beneath the ocean basins and also makes up extensive volcanic provinces on land.
Field identification & locations
Easily identified by its dark, fine-grained matrix and vesicular or dense structure; found abundantly worldwide in volcanic regions.
