igneous
Basalt
Mafic extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark grey to black color, aphanitic to porphyritic texture, specific gravity around 2.9 to 3.0.
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Physical properties
Hardness of 6 on Mohs scale, dark grey to black color, aphanitic to porphyritic texture, specific gravity around 2.9 to 3.0.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the Earth's surface.
Uses & applications
Widely used in construction for crushed stone, road aggregate, and production of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's oceans and forms extensive volcanic plateaus.
Field identification & locations
Identify by its dark, fine-grained appearance and heavy weight; commonly found in volcanic regions and ocean floors.
