igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black in color with an aphanitic or fine-grained texture and dull luster.
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Physical properties
Hardness of 6 on the Mohs scale, typically dark gray to black in color with an aphanitic or fine-grained 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
Used extensively in construction as crushed aggregate, railroad ballast, and in the production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust beneath the oceans 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; found worldwide in volcanic provinces and oceanic crusts.
