igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness 6 on Mohs scale, dark gray to black color, fine-grained aphanitic texture, dull luster.
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Physical properties
Hardness 6 on Mohs scale, dark gray to black color, fine-grained aphanitic texture, dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or near the surface of a planet or moon.
Uses & applications
Commonly used in construction as crushed aggregate for roads, railroad ballast, and in the production of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and also makes up extensive volcanic formations on the Moon and Mars.
Field identification & locations
Identified by its dark, fine-grained appearance and heavy density. Found worldwide in volcanic regions, oceanic islands, and flood basalt provinces.
