igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark gray to black color, dull to sub-aphanitic luster, fine-grained aphanitic crystal structure, specific gravity around 2.8-3.0.
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Physical properties
Hardness of 6 on Mohs scale, dark gray to black color, dull to sub-aphanitic luster, fine-grained aphanitic crystal structure, specific gravity around 2.8-3.0.
Formation & geological history
Formed from the rapid cooling of low-viscosity lava rich in iron and magnesium exposed at or very near the surface of a planet or moon.
Uses & applications
Commonly used in construction as crushed aggregate for road bases, concrete production, and dimension stone.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and is also found abundantly on the Moon and Mars.
Field identification & locations
Easily identified by its dark, fine-grained appearance, often vesicular with gas bubbles; widely distributed globally in volcanic regions.
