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 very near the surface of a planet or moon.
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 oceanic crust and also makes up most of the volcanic islands worldwide.
Field identification & locations
Identify by its dark, fine-grained matrix and dense weight; commonly found in volcanic regions and ancient lava flows globally.
