igneous
Basalt
Extrusive igneous rock
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically dark gray to black in color, with a dull to sub-with a fine-grained aphanitic crystal structure.
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Physical properties
Hardness of 6 on the Mohs scale, typically dark gray to black in color, with a dull to sub-with a fine-grained aphanitic crystal structure.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the surface of a planet or moon.
Uses & applications
Commonly used in construction as crushed stone for road bases, concrete aggregate, and in the manufacturing of rock wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's oceanic crust and also makes up significant portions of the lunar maria and volcanic provinces on Mars.
Field identification & locations
Identified by its dense, dark, fine-grained appearance, often found in volcanic regions, oceanic islands, and continental flood basalt provinces.
