igneous
Basalt
Extrusive Igneous Rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark gray to black color, aphanitic to porphyritic texture, dull luster.
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Physical properties
Hardness of 6 on Mohs scale, dark gray to black color, aphanitic to porphyritic texture, dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in iron and magnesium exposed at or very near the Earth's surface.
Uses & applications
Used extensively in construction as crushed stone for road bases, concrete aggregate, and in the manufacture 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 prominent structures like the Giant's Causeway.
Field identification & locations
Identify by its dark color, fine-grained texture, and high density; commonly found in volcanic regions worldwide.
