igneous
Basalt
Extrusive mafic igneous rock
AI-generated identification · may be incorrectHardness 6 on Mohs scale, dark gray to black color, dull luster, aphanitic to vesicular texture.
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Physical properties
Hardness 6 on Mohs scale, dark gray to black color, dull luster, aphanitic to vesicular texture.
Formation & geological history
Formed from the rapid cooling of low-viscosity, magnesium- and iron-rich lava flows at Earth's surface.
Uses & applications
Used extensively in construction, aggregate, road base, and manufacturing of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forms planetary features like lunar maria.
Field identification & locations
Identify by its dark color, fine-grained matrix, and frequent presence of gas vesicles; found globally in volcanic regions.
