igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness 6 on the Mohs scale, dark gray to black color, fine-grained aphanitic texture, and vitreous to dull luster.
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Physical properties
Hardness 6 on the Mohs scale, dark gray to black color, fine-grained aphanitic texture, and vitreous to dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in iron and magnesium exposed at or near the surface of a planet or moon.
Uses & applications
Widely used in construction as crushed aggregate for roads, railroad ballast, and in the production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and also forms famous geological formations like the Giant's Causeway.
Field identification & locations
Identified by its dense, dark, fine-grained matrix and is commonly found globally in volcanic regions and flood basalt provinces.
