igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black in color, with a fine-grained aphanitic or vesicular 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 a fine-grained aphanitic or vesicular 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, crushed stone for road bases, railroad ballast, and manufacturing stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crustal portions underlying the ocean basins and forms massive geological formations like the Giant's Causeway.
Field identification & locations
Identified by its dark, heavy, fine-grained matrix, often found in volcanic regions, oceanic islands, and continental flood basalt provinces.
