igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness 6 on Mohs scale, dark gray to black color, aphanitic or fine-grained texture, dull luster.
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Physical properties
Hardness 6 on Mohs scale, dark gray to black color, aphanitic or fine-grained texture, dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in iron and magnesium exposed at the Earth's surface.
Uses & applications
Used in construction, aggregate, road base, and production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forms massive features like the Giant's Causeway.
Field identification & locations
Identify by its dark, fine-grained appearance and heavy weight; commonly found in volcanic regions worldwide.
