igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, dark gray to black in color, fine-grained aphanitic texture, and dull luster.
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Physical properties
Hardness of 6 on the Mohs scale, dark gray to black in color, fine-grained aphanitic texture, and dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity, magnesium- and iron-rich lava flows at the Earth's surface.
Uses & applications
Widely used in construction as crushed stone for road bases, concrete aggregate, and in the production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crustal portions underlying the ocean basins and also forms major volcanic features on the Moon and Mars.
Field identification & locations
Easily identified by its dark, fine-grained appearance and heavy density; commonly found in volcanic regions worldwide.
